I could seriously listen to this all day.
The song is a snippet of "Feel It All Around" by
Washed Out, and while I like it just fine without lyrics on the opening of IFC's Portlandia, it's also quite snazzy with the lyrics.
Bonus review of Portlandia: I thought it looked insufferable in the commercials leading up to it, but I gave it a shot and thought it was pretty funny. A solid B, if I was grading Season 1. So if you avoided it for the same reasons I almost did, give it a shot. The first episode is strong like ox.