Tonight I played Borderlands 2. Borderlands is kind of Diablo 2 crossed with a first-person shooter. You play as a Vault Hunter, shooting your way across the world of Pandora. The gameplay is similar to most shooters - you run around and shoot anything that moves.
The twist that makes this game really interesting is the leveling and loot systems. It is very reminiscent of Diablo II as there are skill trees that you expand, and huge piles of randomized loot. Each character class has a special ability that they can periodically active, plus 3 skill trees that add lots of variety.
This is the first time in years that I've enjoyed a shooter, so I definitely recommend it.