Both Wal-Mart and Amazon have already made their positions on DRM pretty well known, but it looks like each are now taking some further steps to ratchet up the pressure on the remaining hold-out record labels. For its part, Wal-Mart has reportedly told the record labels point blank that they must offer DRM-free MP3 versions of all their music, a matter that Sony BMG is apparently still the biggest hold out on. Amazon, on the other hand, is looking to give its download service (and, in turn, DRM-free downloads) a boost by giving away up to a billion free downloads in a promotion with Pepsi that's its set to launch during the Super Bowl in February. You'll need to guzzle quite a bit a Pepsi if you want to get your quota of those MP3s, however, as you'll apparently need to collect five bottle caps for each download. According to Billboard, Amazon has approached all the major record labels about participating in the promotion, but some are apparently balking at the 40 cents per track Amazon is willing to give 'em, which is a sizable cut from the 65 to 70 cents they currently receive.[Via Gadget Lab]