Borderlands 2, last night. It was AWESOME. I'm not usually a fan of shooters but it absolutely blew me away. GREAT characters across the board (Handsome Jack is now one of my favourite game villains ever), exciting and varied environments and set pieces, tight gameplay and of course bazillions of ridiculously crazy guns to collect. If I had to gripe about something it's that the main story takes up too little time compared to the side quests. The side quests are usually very entertaining, but I wouldn't have minded some more exposition, and more backstory for Jack. He was such an interesting character.
Definitely a contender for my favourite game of the year. Working on True Vault Hunter Mode with my Siren right now, and it's just as awesome the second time through.