For those who don't know: FO3 was the only game Bethesda was licensed to MAKE, but they still can PUBLISH the games, which will be happening with FO-OL (probably) and New Vegas.
EDIT: as in, Obsidian (formerly the Interplay division that made Fallouts 1 and 2, Black Isle) is making New Vegas. It looks like Interplay has a big hand in the MMo, though. It redirected me to the Interplay Fallout forums after I registered.