I played about 25 hours of it and got bored, there's way too many "go here fetch this" quests.
To me it seemed like more of a game that requires sheer time and not so much skill, and really isn't that much fun. I like other RPGS that have more guidelines, better tasks, and allow you to become insanely powerful compared to monsters.
The thing I probably hated the most about oblivion was the leveling system was utterly retarded. The game became harder as you leveled up since monsters would level up better than you would. I don't consider harder to be more fun, because it didnt mean that it made the game more challenging, just more frustrating when you can just barely take down a wolf or something.
I find most rpgs where the monsters level up as you level up are dumb. The whole point of leveling up is to become more powerful, so that you can smoke the crap thats lower than you.
Final fantasy 10 is where its at. My main guy can 1 shot almost all monsters, has auto haste, auto phoenix, and autoprotect. That's what RPGS are about to me, getting to a point where you can own ****.
Another sweet one was Diablo 2, nothing was more fun than mowing down 50-100 cows at once.