when ur in a dungeon will u come across bandits fighting the undead trying despertly to hold them back or rivel factins fighting over the dungeon.
will there be adventurers looking for the same thing as u, and will u be able to team up with them to try and help each other get the treauser and spilt it, or after u get the treasur kill them and take it all, those are my queastins.

It's been confirmed that in Oblivion, creatures of people of enemy parties will attack eachother on sight. So if you enter a dungeon with a group of undead and a group of bandits, they won't be sipping coffee over a friendly conversation unless it's some part of a bizarre quest.

Other adventurers? Probably not, at least not 200/200 dungeons of it. Of course, there's going to be cooperative play in the game, but Oblivion isn't a game of consistancy.