I pretty much agree with Bob Lion. It seems like that everything that was wrong with Oblivion was "fixed" in this game. No more two dimensional characters, a lot better writing and voice acting, quests that can be solved in more than one or two ways... It definitely feels more like the first two Fallouts (graphic, combat, and controls notwithstanding) than Oblivion, which is a very good thing indeed. I'll have to play some more before I make any final judgments, though.
Have you tried using any Oblivion mods in the game? Im thinking about trying it. I just have to actually put the files where they go and turn on the game...
Even though the game's using the same engine as Oblivion, the content is different; I doubt any Oblivion mods will actually work. The only "mods" from Oblivion that I'm using is some .ini tweaks and in-game console commands (like changing the game's timescale). Those work because they are more Gamebryo engine than Oblivion related.