Battle of the cloud music services

Google introduced their cloud music service today, Google Music.  In true Google nature, it's Beta.  It's also free for now, but by invite only.  You can request an invite by going to the website.  You must have a gmail account to get one.  Last month, Amazon introduced their cloud music service.  Regardless of which you may choose, the ultimate benefit is that you can now access your music collection anywhere now.  By computer, smartphone or tablet, you can listen to what you own anywhere.  To see how both services compare, check out this comparison chart by CNET.