Wal-Mart has relaunched its struggling digital music store, which will feature DRM-free music at lower prices than what iTunes charges for songs.

The company made the switch to DRM-free sales earlier this year, but as a result had a limited catalog due to holdouts from some of the major labels. That's over now, as all four major labels are onboard, along with various independents, to total 3 million tracks. The store also features exclusive content from Wal-Mart Soundcheck in-store performances.

The standard per-track price is 94 cents, but includes a variable pricing model that offers the top 25 most popular tracks for 74 cents each. Wal-Mart is also offering a free track of the week to promote emerging acts, and will give away a free MP3 download for every CD purchased either in stores or online.

Finally, the online service integrates several new social networking features, allowing users to display their purchased albums on their Facebook or MySpace pages.