I've been addicted to a couple really great musicians lately. You have to check them out.
Mates of State. Love them. They're usually my fave to workout to because they're poppy and upbeat. But "Nature and the Wreck" is their best song, by far. Youtube it.
AND, if their music didn't make them awesome enough go watch this video. They're a mommy and a daddy, too!
Bon Iver. This guy is heartbreakingly rad.
Breathe Owl Breathe. They remind me of my first two years of college at this liberal arts school that was full of patchouli-wearing hippies. Which, of course, is why they are awesome. Listen to "Drop and Roll" and change your life. And did I mention there's a cello. Oh, the cello.
Other good stuff I've been jamming to:
Get Up Kids, New Buffalo, Pinback, The Decemberists, Sunny Day Sets Fire (which I originally thought was a joke/spoof of two great bands Sunny Day Real Estate and Boy Sets Fire - They might be...I haven't uncovered the story of their inception. I only know they're cool.)
As with all music you have the watch the lyrics - I usually do a check of lyrics before I download something. I'm terrible about not realizing what songs are about until they're already emblazoned on my brain and I'm singing them to the kids in the van. So now I have to do the precursory search. I would recommend you do so as well...