I enjoyed Deus Ex, but don't have any interest in playing more of it until the next game comes out in a couple years. I don't even care to try and play it stealth style a second time through (because, frankly, the controls are so fucked and a lot of the AI is so fucked, that playing stealth is like kicking yourself in the junk).

On the other hand, I'm already done with Gears of War before it has even come out and before I've even played it. I'm just so tired of that franchise. It has become a "you play it so you can keep up with the culture" sort of thing rather than "yeah, this is awesome" thing. I barely remember anything about the story in the first two, I don't care about the characters, and the style is kind of grating on me, by now. I hope they stop at the trilogy and Cliffy goes on to do something entirely new and more interesting. The only compelling thing left about the series is that it does tend to have some pretty jaw-dropping set-pieces that will stick with you.