Google Music is old hat. Sorry, guys - it's true. Streaming? Amazon's Cloud Player and iTunes iCloud both have it. Locker storage? Amazon gives you a decent amount, too - and they might even increase it if they feel Google Music is one-upping them. Purchase options? Apple and Amazon both have more music you can purchase digitally, including titles from Warner Music Group (which Google Music does not have), where many major contemporary artists are signed.
Basically, Google did what it had to with Music: it kept up with the competition. Not having streaming, cloud storage, or a major storefront would make Google Music look like a joke next to iTunes with iCloud or Amazon MP3, and this is probably why Google waited so long after the launch of the "Beta" to unveil Music in a more public way.