"The venture goes directly after Baidu's music search audience, by offering high-quality music files embedded with a digital "watermark" that lets record labels track how often their songs are downloaded. The idea: Better-quality files will draw users away from unlicensed downloads, and give labels and search companies valuable data needed to make money from advertising," explained Wall Street Journal.
While the service is now accessible everywhere, you can only download music if you are in China (or if you use a proxy). Google Music has a large collection of music and there's visual tool that lets you find songs by choosing the tempo, the genre and other characteristics.
Except for this regional service, Google doesn't have any full-fledged music-related product. There's a YouTube category for music videos, a very limited music search engine, a music player and a media server for Google Desktop.
{ Thanks, electronixtar. }