Team Fortress 2: I was late to the party, but I've heard how hyped it was. It deserved every bit of it. over 500 hours clocked. bought it last Summer.
Batman Arkham Asylum: Everyone was pissing themselves with glee over this. I thought it would suck. "wait, so Batman is trapped in ARKHAM? HOW FUCKING STUPID IS HE? HE'S TRAPPED... IN A JAIL. WUT.". Thankfully, I was 100% WRONG. GOTY 2009.
Red Dead Redemption: It wasn't EVERYWHERE (not like Portal 2, which I can't WAIT to play, or Batman), but I was still hyped as hell. One of the few games as of late to recieve an actual emotional response from me. It was fun, it was adventurous, it was touching, it was profound, it was BEAUTIFUL. GOTY 2010 and somewhere in my top 10 games of all time.
Pokemon Black and White: I was excited for this. Lots of people were. It wasn't until about a week till release that I realised, "holy fuck. I'm about to play a NEW POKEMON GAME.". THAT'S when the excitement kicked in. The week leading up to launch was pure Poke-mania. It was the 90's again. POKEMON. FUCKING. EVERYWHERE. I was actually somewhat suprised, it EXCEEDED my expectations. It's easily the best since G/S/C (or HG/SS). Great story and I was suprised how much I liked most of the new Pokemon. Great game. Easily lands in the top 10 of 2011 so far.
That's all I can think of atm, hopefully Portal 2, L.A. Noire, and Batman Arkham City will be added to this list in due time.