I agree with Dark Raven on the 3D thing, but not only for characters...many look really great scenic wise, but I'm getting a little tired of seeing the same trees, rocks, building pattern textures, etc. that all 3D games seem to use, it makes all 3D games look the same and thus kinda boring.
At least Oblivion made decent character hands. :D
As to the original post - if you really didn't like MW, I personally don't think you'll find all that much to change your mind in Oblivion. If you sort of liked MW but wished there were some things changed, you might find Oblivion more to your liking.
I haven't played Oblivion anywhere close to the hours of some others here, but IMO it's pretty and has a tigher, smaller 'world' and is more immersive than MW because of it, but gameplay wise, it's still much the same, even w/better quests.