Just like to say that this thread got me signed up for MOG and MY GOOD GOD it's fantastic! It's like Spotify with Pandora radio streams bolted on, but WAIT THERE'S MORE! The radio streams can be controlled so you can choose if the radio stream is all one artist/album/genre or how much other artists/albums to mix in. It has an easy to use slider to control this radio feature.
If I had one small complaint it's this: the play queue does not sync across different browsers or to your mobile device. Each "instance" has its own play queue. A small niggle. Nothing that really detracts from how wonderful the service is. Only other issue is that unlike Spotify, it does not have a local music import feature, so MOG does not know anything about your local music collection. Which is fine because Spotify does not see flac files anyways so Spotify cannot see my music collection anyways, big boo for Spotify.
AND it's all 320kbps ogg streaming!