Quake Live 
Battlefield Heroes Overall Comparison Now that I got to spend significant time with each game...
Quake Live currently offers a better game service, I feel. I'm not gonna be picky about wait times and beta access and such cause that's unfair, but I like the mechanics and style of Quake much more.
Quake is faster paced than Battlefield. While Battlefield offers vehicles, it doesn't offer much in variety of weaponry. In fact, BH is a pain because you have to earn points within the game to buy weapons for your character. Sometimes you even just RENT the weapons for a few real-world days. This puts you at a serious disadvantage when you just start the game.
BH does allow you to customize your character with a variety of features and clothing, so thats a plus. However they don't seem nearly as unique as Quake's characters. However neither game really has a serious graphical advantage over the other. They're each stylish in their own way.
2
1
3
Comments
Do you think that, as you play more, Battlefield Heroes will become better than Quake Live because of the upgrades you'll have? Battlefield Heroes seems like a game that will get better over time, whereas Quake Live will always stay the same.
I generally prefer the fast-paced arcade-style action of Quake and Unreal, though.
I do bet that the game gets more fun as you earn more weapons, but even so I prefer a game where someone can actually be better cause they can play better, not because they played so long that they have all sorts of upgrades.
I'm a huge fan of the pick-up-and-play, fast-paced deathmatch stuff. I remember playing Deathmatch Classic for Half-Life and I loved it.