Fallout 3Oblivion with Guns
Not really. The leveling mechanisms are entirely different, to where you actually feel like you're making progress in Fallout. You don't just walk around jumping into firepits, either - encounters in the environment will sometimes just kill you. Plus, it has a more substantial plot.
As much as I loved Oblivion, I felt Fallout was a much better game, all around. Like I said, I actually felt like I was accomplishing something, not just jumping into firey holes for 10 hours.