I've played the game for the last week or so (interupted by a dead videocard, brand new), and so far i'm impressed. Sure it's different from Morrowind, but so far it's an improvement. I visited some "tombs" in Oblivion, and had to navigate around traps, which is pretty cool. I also had to run like hell for a couple of zombies (first level, gimme a break!
. Then, to add insult to injury, those zombies followed my out of the tomb to attack me outside, which never happened in morrowind. I'd say those changes alone make the game much more realistic. As for the combat... I now feel I'm actually fighting for my life instead of just whacking around.
Morrowind was great, no doubt about it (I've seen pretty much every inch of the Morrowind lands, including the expansion packs); but Oblivion is a whole new game to discover!
(By the way, I also played Daggerfall, the eldar scrolls 2. When playing Morrowind, I was always annoyed that that game wasn't as huge as Daggerfall. There's always something to bitch about, I guess.