After getting somewhat burned on Oblivion, I started to be a little pessimistic. Then Shivering Isles game out. While there was a lot wrong with Oblivion at it's very core that couldn't really be fixed, they addressed the primary issue I had with the game through Shivering isles, the attention to detail. Obviously they couldn't patch that in the rest of the game, but still.
Fast forward to Fallout 3. It suffered a lot of the core faults of Oblivion, but faults that really had been present beforehand. Most are petty gripes like a punishing lack of diversifying options. But, through the whole world, they had addressed my big complaint. The world felt alive. You could wander, and see echoes of the past, and not just the husks of the buildings ravaged by the apocalypse. Recent stories that tell through context, rather than through brute force. Follow a blood-trail into a building, find spent Microfusion cells, a tipped over table, one dead Paladin with his Holotag missing. In front, a small group of mutants, some ash piles, some still fortunate enough to have bodies. Further in this building, a dead Paladin with no head, next to him, more spent Microfusion cells, and a dead Super Mutant with a Sledge. Head down the hallway and out the door, and a few steps from the door, another dead Paladin, with his brother's holotags in possession, cut down by a Super Mutant position across the street. Not a single word was said, yet a harrowing tale was told through context.
That is what was missing from Oblivion. The world felt Sterile, but it's apparent through Shivering Isles and Fallout 3, that Bethesda has learned. And I can't wait to see how the lessons are applied in Skyrim.