Google has been deep in talks with record labels and hopes to have the new service up and running by Christmas. Google’s new service would be an iTunes challenger that would be deeply connected to the Android mobile operating system. Google plans to first launch a music download service and progress to an online subscription service by next year. Ultimately, Google Music would be a cloud-based subscription service with the ability to stream directly to Android mobile devices.
Amazon was not a great iTunes challenger, but Google might be the one.
iTunes is not a centralized Store, its music library varies from country to country, it doesn’t live in the browser but in iTunes, and recently various US accounts from outside the country were banned from the Store by an IP control policy.
One more service in the music world implies better offers, prices and services for the customers 
Google Music China:
