I'm honestly not much of a fan of games that you can continue after having finished the main quest and all - because, well, let's face it, a single player game can never be quite a "second life", no matter how much one wants to. Sooner or later one'd become bored with the endless fetching quests, the world staying never-changing, a lot of things being impossible to do and so forth. Much better to do the main quest, reach the climix of the game and then have a satisfying ending which gives a hint or two on your fate based on what you did in the game and then tells you how the world fared thanks to/because of you during the course of the game and beyond it.
I'm quite optimistic here too, because I don't think they're going to repeat the stupid thing about Fallout 3 either. What I, at least, disliked about FO3 wasn't so much that my character had to die but that he had to die when often enough, a third (and more sensible) option was available (Fawkes, Sergeant RL-3, Charon). In short, I disliked that the game forced us to play as either the "heroic" guy (in the discword sense - which translated as outright stupid) or The Jerk (who made Sarah go instead), instead of "The Guy who wants everyone to survive AND come out alive himself", sorta. In short, they completely ditched the Third Option, which is something they shouldn't have done and this is something they fixed to everyones (?) satisfaction witth the Broken steel DLC.
Now, knowing that Obsidian is both aware this AND has some experince at implementing The Third option, plus nicely summarizing the effects of your actions in the en ding (I'm looking at you, Mask of the Betrayer!
I only hope they have sutitles present at the ending though. FO3 didn't... (neither the intro
