N. Wright at Lawful Indifferent has a piece up about preferring anti-heroes to heroes, and adventures to 'saving the world.'
I agree that 'save the world' plots in RPGs get old quick. They're fine every now and then, for HIGH LEVEL PLAY. But so many GMs I see or read about want the whole damn campaign to be about this great quest with the goal of saving the world, a la LotR/Dragonlance/whatever Final Fantasy game they've just played.
When it comes to the adventure, I'm really more interested in the episodic, picaresque, motivated by personal self-interest type things. Like REH stories, or Lieber, or your typical B movie plot.
HOWEVER, I do enjoy having characters that are more like Galahad, Luke Skywalker, or the Lone Ranger in the mix. If everyone's an anti-hero I'm less interested in things. And in my personal gaming experience in the past 10 years or so, I don't see many characters like this (even when someone's playing the Paladin).
Now, I'm not saying I think a party of all stand-up, dependable, honorable characters would be best. It might be fun for a while, but having a mix of characters in the group is where there's the most fun.
Compatible, but sometimes at odds. That's fun. And more dramatic.
Luke and Han don't always see eye to eye, but they are friends and can work together. Same with Batman and Superman.
You need a few heroes out there to make the anti-heroes meaningful.