Wal-Mart has reportedly demanded that the major labels release more of their catalog in DRM-free MP3 format, apparently buoyed by the relative success of their DRM-free MP3 store (at least when compared to the red-ink-fest that is every DRM music store except, perhaps, iTunes).

In a bid for more of the digital download space, the brick-and-mortar retailer heavyweight has reportedly given an ultimatum to some of the largest record labels, including Warner Music Group and Sony BMG Music Entertainment, to provide more of their respective music catalogs in MP3 format (that is, without DRM) next year.

Link (Thanks, Glyn!)