My only real gaming obsession, the Halo series.
I've just got the latest, the Halo 3 expansion ODST (Orbital Drop Shock Trooper), moving away from Master Chief to instead follow a normal-ish UNSC soldier.

Game play wise, it is very similar to Halo 3. The two main weapons of the main character have been changed, which I think is great. But you have a health bar instead of fully regenerating shield, which can be frustrating.

I really like the story line and graphics. Especially since the cast of Firefly/Serenity is included (Mal, Jayne and Wash), and the player gets to play as them all at different points (Actually, I'm not sure if Wash is one of the characters I have found yet). And the whole game is much darker and less of a sci-fi technology orgy than the other games, set on earth.

...When I started that, I wasn't intending it to be a review. I've forgotten what I was originally going to write about. Anyway, it's a good game.