I think your views of Oblivion and other RPGs (if you for argument's sake would be willing to consider Oblivion as an RPG for a moment) are clouded (if that's the correct word?) or influenced by what your definitions of rpgs are.
If you mainly focus on the story-telling aspects
of the rpg genre as well as the character interaction, dialoque choices, skills and stat based aspects of
the genre, then you may not find that Oblivion is an rpg.
If you, however, mainly focus on the open exploration, the ability to go anywhere you can,
whenever you want to do it as well as the ability
to join several factions and such things, then Oblivion is an rpg.
Personally, I would like both sides of the coin, if &
when it is possible. However, I'm realistic enough to know that this isn't always possible.
I like Bioware's storydriven (linear) games with their focus on character creation as well as Bethsoft's games with their focus on exploration and non-
linearity.
However, as I've stated before, I don't think that neither Morrowind nor Oblivion are the bestest rpg games evar. I have voiced my constructive criticisms of Oblivion both here and on the ESF boards.
I've once read a review of Oblivion in the Danish Edition of PC Player in which Oblivion got an 8/10
rating which I thought was a fair rating.
One of the big problems I have with Oblivion is
that there doesn't seem to be any people in its
cities, towns and villages. Another problem re: Oblivion for me is that Oblivion cities are way to polished and lacklustered, to my taste.They simply looks to nice to be true.
As for the new expansion; the shivering isles,
I agree that the world seem a bit more morrowishness, but I think that this has to do with the realm in which the story takes place.
Apparently the shivering isles expansion takes
place in another realm than ours which means
that the devs. can use their imagination a lot, creating colourful worlds as well as dangerous, dark and sinister places in this world.