Before we begin, allow me to indulge in a brief preface. Hellgate will not be the end of the World (of Warcraft). Despite popular perception, it is possible for MMORPGs to coexist, especially ones with vastly different settings and gameplay styles. All other technical reasons aside, such talk is nonsense for these reasons alone.
That said, we begin our match.
Round 1: Launch
Warcraft had a number of issues at launch, some of which were so severe the game lost several awards it had received. In summary, there were numerous minor glitches and rampant server stability and reliability problems. By the time I picked up the game these had been dealt with, but that was six or so months later.
Hellgate, similarly, has issues as well. While it shares in the numerous small glitches, Hellgate lacks the rampant server issues of Warcraft. Instead, Hellgate has various minor nuisances throughout its user interface and instruction.
Explanation: By all accounts the glitches are pretty equivalent, leaving the judgement to a measure of server issues against interface problems. Here Hellgate might seem to come out ahead, as server problems prohibit play entirely while a slightly unwieldy interface only makes play more difficult. However, server issues are more readily repairable. A later judgement may be able to better weigh this contest, but for now it shall be judged that the one is even to the other.
Round 2: Character Creation
The character creation systems in both Hellgate and Warcraft are remarkably similar. There are very minor differences, but someone who has seen one can very easily understand the other.
Hellgate has several advantages, and a small disadvantage over Warcraft. Rather than cycling through hair and skin colors, Hellgate has a drop down palette that makes such choices far easier. Where Warcraft has races to differentiate height and breadth, Hellgate has sliders to allow for that kind of differentiation. Both games have class and faction descriptions present.
Where Hellgate errs is in the depiction of the character. Rather than show what your character will look like initially, the game shows them as they might look in higher level gear. This can be confusing, as it isn't clearly stated anywhere a casual person might look. Some people might see this as an advantage, but for the most part it is more of a hinderance than a help.
Explanation: The color palettes are nice, but it's as minor as the depiction mistake.
Round 3: Initial Impression
Warcraft treats you to a sweeping tour of your character's starting area at the offset complete with dramatic voice over explaning your backstory and place in the world, before dropping you in front of your first quest giver. From there, you are asked to embark on your first genocidal quest to cleanse the area of some unfortunate animal, and slowly familiarize yourself with the game's basics. Any tutorials are in the form of tips at loading, or clickable during the game.
Hellgate's backstory is almost completely conveyed by the game's opening cinematic. Your place in the grand scheme of things is explained only in the manual. However, Hellgate's tutorial is somewhat more proactive in helping you get a feel for the game. It's very friendly, very helpful, unrestrictive, skippable, and short. Basically, everything you could want from a tutorial. There's are a number of things that aren't covered, but Warcraft is more than guilty of this as well.
The impression Warcraft impresses upon you is one of awe and an eagerness to explore. Hellgate, on the other hand, is more content to let you be excited about your character and their abilities.
I'm going to fault both, however, in that neither really take care of their own. Beyond the very most basics of the game, very little is explained. It's enough to get a player unfamiliar with MMORPG conventions up and going, but it leaves them to flounder about every which way. Each has their highs and lows in this area, but neither really comes out on top.
Explanation: While we could argue that Warcraft's interface is more intuitive and thus user-friendly/impression making, that's a separate round unto itself.
Round 4: Interface
Mods are excluded from this round as outside parties. I will not delve into them, nor into the ability of either game to support them. Should it come up, it will be in the inevitable rematch.
Hellgate's interface, as one might guess from earlier notes, leaves a fair amount to be desired.
First and foremost, the game has issues remembering your account name. It will only keep track of it so long as you do not exit the program. Even in this case the cursor defaults to the account name field, meaning it must be moved lest one absent mindedly start typing their password in the wrong place.
The next obvious failing is that of the helpful tips on the loading screen. Specifically, their propensity to burn through several hundred of them in less than a second during the loading process. This, however, only obscures the complete lack of any visual measure of loading progress for a minute or two. While the loading screen is aestetically pleasing, it would be nice if some indication of the current status of the effort were present.
Also vexing the user is the method of logout. If one wishes to stop playing, the "Exit Game" option is chosen. Rather than exiting the game, however, it only pushes you back to the log on screen. This appears to be some deranged compromise between actually exiting the entire game, and providing an option to exit to the character selection screen. As it stands, a player must "Exit Game" and then log in again in order to switch characters.
The other notable nuisances are the lack of any efficient system to trade items between characters, the unintuitive and obfuscated choices in console commands, and the similar difficulty in item management. There isn't any way to transfer items between your characters save for handing them off to a trusted friend and relogging. The console commands, while following the standard /[command] syntax are longer in name than necessary and are not described either in the manual or in the game. Lastly, Warcraft has a universal key one can hold down while clicking to move the chosen item into a bank, buy or sell from a vendor, or trade it to another player; Hellgate only has this function for vendoring.
Meanwhile, Warcraft boasts mailing systems, an auction house, helpful guards, and will soon sport an enhanced minimap to make finding quest givers, trainers and vendors easier. As a whole, the Warcraft interface is also intuitive and consistant. If something functions in one place, it functions the same way elsewhere. It also mimicks standard operating systems enough that there aren't any surprises for anyone.
Judgement: Warcraft wins the round.
Explanation: Hellgate's glaring errors don't impact actual gameplay, but they make getting to the good stuff significantly harder than necessary.
Round 5: Gameplay
Warcraft and Hellgate come from two vastly different schools of thought in terms of MMORPG gameplay. Warcraft follows the tried and true Everquest paradigm, while Hellgate sticks to the roots of its creators and takes after Diablo. Both styles of gameplay have their merits and their detriments.
Warcraft's gameplay is much more forgiving to the player, but much less so towards the player's time. Most notable accomplishments in the game take a significant investment of one's free hours. It is possible to spend hours just preparing for some other task, and getting nothing done other than "housekeeping".
Timewise, Hellgate can be played in short spurts or over large sessions. While it has similar directives to Warcraft, the time between setting out to complete a quest and returning victorious is far shorter unless you are going in over your head. The lack of a cohesion in Hellgate means the game doesn't suffer under the need to establish a sense of distance in a persistant world. As such, all of the traveling around to find vendors and services is absent. The presence of instant teleportation to other party members, and to and from town, significantly shaves off the time investment required.
Additionally, the pacing of each game varies as well. The actual meat of each game, quests and killing of monsters for loot, experience and glory, follows the same pattern. Warcraft has a much more leisurely pace, while Hellgate is more action oriented without necessarily being more difficult. Hellgate's leveling curve is far more forgiving than Warcraft's as well. They both start out even, but where Warcraft's begins to slow Hellgate continues to charge forward at relatively the same rate.
Hellgate is also far more forgiving when it comes to items. There is no concept of "soulbound", items can be freely traded and reused. Items are easily upgraded, customized, added to and more. While Warcraft has significant crafting advantages over Hellgate's professionless system, the freedom Hellgate offers is an unavoidable advantage.
Warcraft, however, is more forgiving in one area. Hellgate offers no ability to reselect skills and spells after they have been allocated. Once you have made your character choices in attributes and proficiencies, there is no going back. This does, however, suit Hellgate as it did its predecessors. While for a beginning player the time necessary to level a character will be significant, experienced players will likely be able to reach "high" levels over the course of a weekend.
Judgement: Hellgate wins the round.
Explanation: While actual judgement of the respective gameplay styles is subjective, Hellgate has a key advantage in allowing you to get from login to gameplay much faster and without as much effort. The "Time to Fun" as it were, heavily leans towards Hellgate.
Round 6: Social
Warcraft is an odd duck when it comes to matters of society. It seems to preclude having a social life, while at the same time being a heavily social game. It encourages bonding with other players, while seemingly attracting the kinds of people who fail to realize that "plz" is not an endearing subsitute for "please".
However, the kind of bonds that form from grouping and raiding in Warcraft are not easily replicable in Hellgate. There isn't content in Hellgate that makes deep friendships a commonplace thing. You don't have the same kind of dungeons, raiding and group questing that bring people together. Rather, Hellgate is more oriented towards incidental fun with friends you already have.
Explanation: To summarize, Warcraft is a much more social game but comes at the cost of social life elsewhere. Hellgate may not have as much social depth, but it does allow for it in a more casual sense and at the same time does not have any draw to preclude other social engagements (beyond basic addiction).
Bonus Round: Overall
We could try and compare Warcraft as it was against Hellgate, but that's a bad comparison. Whatever Warcraft was, it has since evolved. Telling people that Warcraft was a fun game nearly 3 years ago is about effective a suggestion as telling people how wonderful this town was before all the carpet baggers came. The suggestee can't take a bus back to yesteryear.
As such, Hellgate must face off against the Warcraft of today.
Judgement: Warcraft wins the round.
Explanation: The amount of content, it's quality, the long fixed bugs, the smooth servers, and the excellent interface come together into something spectacular. Should Hellgate improve on its shortcomings the same way Warcraft has, it could easily boast a victory later. For now, Warcraft is the better experience.