Thank you so much for this! It's just a Safari wrapper, but it's the first native solution I've seen. Google is really horsing around with Google Music, it's sad that I pay them the same amount I would (and did) Rdio and Spotify and get treated with shitty Flash web players and no native apps.

edit: 15 minutes in – it's not extremely polished but I really love it! Finally, no more annoying music.google.com Chrome tab.