I've been playing Red Dead Redemption which is fun, but it is basically Grand Theft Auto set in the wild-wild-west. So I don't know if it fits your definition of "plot driven" but there is a plot none the less...

I agree with Red Dead Redemption. It is GTA like in that you can either drive the plot or see how many bodies you can pile on the train tracks before the 3:10 to Yuma comes through, but the acting and story are very good. The promise of add-on story lines gives some future replayability.

I assume you've played Fallout 3, but I'd say that's in the same boat.

Yes, I have the "Game of the Year" edition of Fallout 3 - loved that game.

If you are looking for plot driven and don't care if it is an RPG, then I would have to agree with the recommendation of Red Dead Redemption. The story is great and the ending is pitch perfect.

If you haven't played them then Oblivion, Fallout 3 and Fable 2 are all worth a few (hundred) hours. I am playing Assassin's Creed 2 for the second time and while the story isn't an award winner it also isn't bad and the platforming is fun. If you are at all a fan of Batman then Batman: Arkham Asylum is a blast.

As I wrote in a comment to the Mass Effect summary post, Alpha Protocol can be recommended, provided you are ok with its shortcomings :)

f you haven't tried it yet, Mask of the Betrayer (NWN2 expansion) is probably the best plot-driven game I've played in the last few years.