http://www.xbox360achievements.org/news/news-3293-Alpha-Protocol-Can-Be-Completed-Without-Killing-a-Soul.html
Apparently it can be completed without killing anyone at all. Presumably you can arrest the final boss or something similar. Or perhaps there is no final boss or maybe you kill him in a cutscene where you have no control and they're not counting that since its not yoour choice.
Sounds like the game just got that little bit more awesome in any event

I suspect what they mean is that there are non-lethal methods available (nightsticks, tranquilliser darts, Vulcan nerve pinches, whatever); when you use such methods you aren't killing anybody, but the end result--all targets down--is exactly the same.

And the sex will be satisfying and tasteful. Truly the mark of a great game.

I wasn't too into this, but now I'm kinda excited. :)

Well you wouldn't want bad sex in a game, that'd suck
and not in the good way

I don't know about that. If a game had a sex scene that was horribly executed (The Watchmen of sex scenes), it may convince many critics that games can be on the same level of artistic expression as movies are. I suspect that there will be a sex scene in Heavy Rain, and I think that game may break giant barriers in the "games as art" argument.

There are still people seriously debating whether games are art or not?

Yep, sadly. Games are art.

The trailers and gameplay videos make the game seem ultra cliche.

My thoughts as well.

Games can be art -- let us not confuse.
And yeah, that Watchmen sex scene was the worst I've ever seen in my entire life.

The developers say they were inspired by the three "J"s: Jack Bauer, Jason Bourne, and James Bond. How's that for cliché? :)

Well, it's an RPG so it could be worse. It could be a D&D-game.

I think the only two games I knew of which you could complete without killing anything/anyone was Fallout 1&2 and Deus Ex. Anyone know any more?