Look at the prices as of today:
You can even get more storage. This means you could store 200 GB of music for just $50 a year e.g. That's right, a year! With the amazing Android-app you could stream it directly. No need for big memory cards anymore. I'm sure apps for other mobile phones will be announced, soon.20 GB ($5.00 USD per year)80 GB ($20.00 USD per year)200 GB ($50.00 USD per year)400 GB ($100.00 USD per year)1 TB ($256.00 USD per year)
No plans have been announced, but it's possible, since all the storage can be used from all the products. If this won't change, it's one big thing. I'm holding all of my plans until it's official what is happening with Google Music, and if you can add your own music, you already bought or sampled from your CD-collection.
Another service does already have music-streaming to Android and other devices is GoAruna (<-Ref. Link) ( =^.^= ) . Their app is fantastic and also usable for written stuff. Prices are okay, but it shows what game-changer Google would be. Prices are way more expensive. On the other side GoAruna already does good and even supports different formats, like .ogg (vorbis) files to stream to the browser (only Chrome here with Ogg vorbis), or mobile. It works good. You can give it a try for free with 2GB of storage.
However, Google Music is the big thunder many are waiting for. It could be really big. In my opinion it all rises and falls with the ability to upload your own music. If you need to buy everything at a "Google Store" and only this music is stored to stream to your device, it's dead meat. Let's see, I'm curious.
I want to be honest: The links to GoAruna.com in the article are Ref-Links, giving me 250MB more for free if you choose to register (=^.^=). If you don't want that, please use the direct link to GoAruna.com, or type it in the browser bar.