Gotta be Fallout 3. That game just compelled me to completism. I wanted to see every corner of the wasteland, and do absolutely everything there was to do. And even so, I've only followed the good karma path, and have still never done any of the slave missions, or any of the other bad-guy-path stuff. And of course, once the game is over, there were five bloody packs of DLC to chew on. Not to mention that as a sandboxer, I keep coming back in just to tool around. I haven't done that since GTA San Andreas...Which I STILL pop in and fart around with once in awhile.
It's funny - you play these games long enough, and you get to the point where you know the environment as well as any real, meat-space area. You know the corners to turn to get to your favorite areas, and the places where you've stashed gear to come back for it later. As the realism grows, so does the sense of place. Some days I come back to "my" house in Megaton to dump off a bunch of plunder in the locker, and I genuinely feel at home before I go upstairs to save and turn in for the night. At which point, I ACTUALLY go upstairs and turn in for the night.
Point is, New Vegas had damn well better be stupid awesome.
It's funny - you play these games long enough, and you get to the point where you know the environment as well as any real, meat-space area. You know the corners to turn to get to your favorite areas, and the places where you've stashed gear to come back for it later. As the realism grows, so does the sense of place. Some days I come back to "my" house in Megaton to dump off a bunch of plunder in the locker, and I genuinely feel at home before I go upstairs to save and turn in for the night. At which point, I ACTUALLY go upstairs and turn in for the night.
Point is, New Vegas had damn well better be stupid awesome.