If you have root, then be careful. If you authorize 10 devices (different ROMs) to your Google Account, then you can't add any more. It used to be as simple as deauthorizing devices every time you reach you limit. As of now, you can only deauthorize 4 device PER YEAR. Be careful...I just had to reupload all my music to a different account because of this.
MEGA SUPER ULTRA EDIT: Google appears to have fixed the issue. Both Adrynalyne and I can now deauthorize devices. It still says the 4 device restriction applies, but seems to be fixed. YAY GOOGLE!