Obama Wins the Nobel Peace Prize

I just don't get it. Can someone please explain to me why Obama won the Nobel Peace Prize? He hasn't even been in office for a year, and hasn't done anything really substantial. What is the thinking here? I really just don't get it. Is it because he's the first black president? Is that reason enough to garner the Nobel Peace Prize? I thought the Nobel Peace Prize went to people who changed the world or life as we know it. It's for the Ghandis of this world, for the scientist that makes a breakthrough in the fight to cure cancer, the guys who mapped the genome. What has Obama done that puts him up on that level and makes him deserving of the Nobel? Someone please help me make sense of it...