Oblivion managed to improve on a couple of areas. However, it seems that they might have taken a few steps back as well. The overall simplification, or “streamlining”, if you prefer, of the game I don’t think makes it feel quite as in depth as Morrowind. The interface itself has a couple of oddities that don’t quite make sense for the PC environment either. While I am sure that, overall, it is still a decent game, I think that history will look at Oblivion as a step back in terms of “openness” for the series.
It already doesn’t look like the replay value will be quite up there with Morrowind, but it should still be a decent romp for a while.