@Kinackin: I like a lot of games for their story, and as such will usually finish the game so that I get all of the story, but the completionist nature of things you are describing is what initially made me very worried when Microsoft first announced the whole acheivement/gamerscore thing and would ultimately take a lot of fun out of gaming and replace it with needless competition; luckily it hasn't affected me in this way and has instead served as an encouragement to go back and get more out of the game sI really enjoyed and think are worth going back for acheivements/trophies.
In conclusion I don't think it's so much acheivements and trophies that mean we (or at least I) need to finish just that as games are developing many of them are becoming more plot driven and have stories you actually care about and want to find out what happens, as well as fun gameplay. Obviously some games e.g. Burnout, Street Fighter etc. aren't really about story, but then I'm only driven to play them for as long as I find them fun and acheivements haven't really changed that (as you can probably guess from my mere 80 points on SFIV).
I suck at fighting games; I enjoy them, but not enough to get good, although I did used to be the best Tekken 2 player among my friends as a kid. To a certain extent that's probably true of online shooters too as I haven't played for ages, but it wouldn't take me so long to get back into the swing of it (at least I hope not as I've been meaning to get BF:BC2).
@EliasT: If I have to pick I'll go with consoles because I'm not good at keeping on top of hardware updates with PCs and I prefer a gamepad to a mouse and keyboard, but really I enjoy and use both, and some games work better on one over the other.
@Porcelain_Snake: Probably when I got concussion playing rugby with a bunch of people who were older than me at school, and a about three of them land on top of each other with my head at the bottom of the pile. I was sick a lot, went to hospoital and had two X-Rays and a CT scan.
@erinfizz: Like most of these types of things, it seems to be more about fashion trends and attitude than anything substantial, some bands just get lumped in with trends like hipster, or emo (which started off as a genre but has become a fashion statement). This is why I don't listen to music until it's been around a while so I can correctly classify and categorise it.