The Digital Freedom Campaign, an effort backed by the Consumer Electronics Association, Public Knowledge and others, lauded the move. "In the fight for consumer rights in the digital age, the tide has clearly shifted,” spokeswoman Maura Corbett said.

Wal-Mart gained its mega-store status "by putting their customers first and offering the products they want." Then the company "took that philosophy digital," she said. Corbett said the action could be a precedent-setter and urged other retailers to follow Wal-Mart's lead.

The DRM-free music will be available for $0.94 per track and $9.22 per album -- lower than most offerings from Apple's popular iTunes service. Wal-Mart will continue to provide its existing WMA-format music downloads for $0.88 per track.

The new format will give customers "the ease and flexibility to play music on virtually any device at a great value," said Wal-Mart Senior Director Kevin Swint. Read Wal-Mart's press release here.