#5 Diablo 3 - Honestly, this game could easily get up to number 2 and possibly number 1. The only reason it's so low on the list right now is because it's only a month old. Too soon to see if the lasting appeal is there. I've put over 200 hours into the game I'm still addicted.
#4 inFamous - My favorite superhero game of all-time. Surprising considering how great Arkham Asylum/City are. This one blew me away and stands out as a sandbox game I can actually tolerate.
#3 Metroid Prime 3 - My favorite Wii game. It's not as memorable as Prime for Gamecube, but it is the most fun and replayable of this franchise.
#2 Dragon Age: Origins - Fantastic memorable story and characters. Moments in this game are etched in my mind like classic moments in movies growing up.
#1 Rock Band 3 - Favorite game of all-time which makes it the default winner for this generation. Guitar/Base/Vocals/Keyboard are okay, but Drums are fantastic. This game is fun solo, multi and co-op and provides the greatest sense of accomplishment and replay value I've ever seen in a video game. I only wished the drum sets weren't so fragile as the pads tend to break down in about a year.
Honorable Mentions: Civilizations 5, Plants vs Zombies, Mass Effect 2, Dragon Age 2, SWTOR, Defense Grid, Zelda Twilight Princess, Borderlands and Super Street Fighter 4