I like big interfaces. Big but discrete is something I strive for. Sure, the smaller the interface is, the less it gets in the way, but it's downright annoying to have to divert your attention from the action in order to see how much more you can take. FarCry Instincts keeps killing me EXACTLY all the time for that reason. Tiny tiny digital health meter...
I quite like the new one with the big throbby heart. Except, supposedly realistic renditions of internal organs make me feel funny. I'd prefer just having colored bars and nothing else. Or, like, a cool icon if the game has some sort of logo. A shiny knife with blood dripping from it, and the dripping blood creates the health bar. That'd be awesome.