I liked Oblivion for the first 8 hours and then it fizzled out with cookie-cutter dungeons and too easy combat. I'm playing Fallout 3 now and enjoying it, but I wonder if 8 hours of gameplay later, it will end up too easy and generic like Oblivion ultimately was. Just saying that first impressions of a game arent reliable.
So far every location I've been or "dungeon" has some kind of story attached to it. The combat in each place might be similar but the added story makes it all more interesting. It gives you a purpose and a sense of discovery.