Bethesda is holding an event right now in London it seems, where one of the big announcements is that they've hired game studio Obsidian to work on a new Fallout 3 game, which won't be a sequel (probably a parallel story). The game is titled Fallout: New Vegas and will presumably take place in Las Vegas.

I love Bethesda and Fallout 3, but the idea of Obsidian (who did the second KOTOR) doesn't fill me with joy.