Amazon’s online music store Amazon MP3 got a significant boost today through an agreement with Warner Music Group. It now offers Warner’s entire digitized catalog for download, bringing the number of DRM-free tracks available on the online music store to 2.9 million.

All songs offered through Amazon MP3 are encoded at 256 Kbps and priced from 89 to 99 cents, with most albums priced from $5.99 to $9.99. They work on virtually any music player—including the iPod. And although its catalog is still smaller than that offered by services selling DRM-protected music such as iTunes, it is nonetheless an indication that DRM-ed music may be coming to an end, and that’s a very good thing for music and gadget lovers alike.