Totally with you. Cute idea but pales in comparison as a listening experience to Pandora.
However - if they can get some brand-name DJs on there with a known style (or grow some) I think the value prop changes for me. Right now it's "experience what it's like to be a cool dj!" Which is great for the dj but bad for everyone else in the likely event that the current dj is not in fact a 'cool dj'