But what's special with the interaction in Oblivion, making it so original from other rpg's?
Well, the closest thing to it is Morrowind. The vast majority of RPGs don't give you a wide open map and allow to go anywhere before you've even levelled up. With most RPGs, there's a bit of funnelling involved. The fact that you can completely ignore the main quest and still plough 100+ hours into the game makes it fairly unique.
The first person perspective is also fairly unconventional - yes, there are others that use it, but none of the examples I can think have the same go anywhere/do anything aesthetic.
Granted, most of the stuff you do in Oblivion you do in other RPGs - speak to NPC, get quest, do quest, get reward etc - but the execution is different to most.
I have never played an RPG like Oblivion aside from Morrowind. Some of it is difficult to put into words, but there's something about the way Bethesda do things that makes their RPGs unique, immersive experiences. And it's very evident from the recently released PAX demo that Fallout 3 carries the very same Bethesda hallmarks.
It's not "Oblivion with guns" because it's the same engine. It's "Oblivion with guns" because it appears to carry the exact same design ethos with a different visual style and a few extra bells and whistles.
Exactly. Whether or not we agree on if that's a good thing, it's pretty obvious where the comparisons lie.