Wal-Mart jumps on the DRM-free bandwagon

Ars reports that Wal-Mart's online music store now sells DRM-free music from both EMI and Universal.

Given that Wal-Mart is the world's largest music retailer, and that they clearly see value in being able to market the music as ready to "play on the ipod", how long before they force Warner and Sony BMG to follow suit ?

Hopefully it's before our government decides to enact our own version of the DMCA...