Word is that Google is planning to launch a music service and according to sources quoted by TechCrunch, the company is securing content from major labels right now. One source calls the service “Google Audio”.

It’s unclear if this music platform will be download-based like iTunes, or streaming-based like Pandora, but apparently it will be available to “at least” the US. Google already has a music service in China that lets users download tracks for free, and it has a music search engine that can be accessed by typing “music:” before your query in the search box. However when you access a song that way they aren’t available to listen to.

Amazon today announced plans for an international rollout of the Amazon MP3 music download service to take place sometime yet this year. This announcement is probably the biggest threat to Apple’s mammoth iTunes to date as it likely to cause the reining media download leader to make some changes in coming months to keep up with the competition.

Once Sony BMG came onboard Amazon became the only online retailer to offer downloadable MP3’s from all of the four most major music labels that are all also DRM-free. Amazon MP3 now boasts over 3.3 million songs available with no restrictions on what player or computer the songs can run on, and no restrictions of how many places users can copy it to.