I had transferred my music files over to Andrea (TF101) from Alice (netbook), and after getting my invite, I transferred them over the work group to my gaming system, so I could add stuff via the PC media player. So I decided to clear my /mnt/sdcard/Music directory and reclaim some disk space, since I rarely listen to it all and I have other copies of the data.
Pretty much, I ended up with a Google Music app still reporting the local data and force closing on playback, even after stopping the service and clearing the apps data. After a little Google fu to see if it ought to work, I rebooted into recovery and hosed the dalvik cache; one perk of being root.
Now it works perfectly, and I doubt I really need a gig of files laying around so Google Music is an idea I like. Even more so because I tend to listen to radio streams more than I buy music, hehe.