I upload my music to Google Music. But just so I can access it when I want to play some music when at a friend's house. It just don't work on my mobile phone, because when I leave my house I got no mobile connection, so I NEED to rely on music saved on my phone already. And why I don't use it at home: My local music player (mpd) makes it so much more comfortable (shortcuts, remote control via phone, ...)