Warner Music Group – the last DRM holdout – has caved in. Edgar Bronfman, WMG ruler and DRM’s most zealous champion has reversed his position and become the latest MP3 Lunatic. WMG has made its catalogue available at Amazon MP3.

The Lunatics note 2007 has seen all of the major labels finally embracing the MP3 format.

Does this mean it’s finally last rites for DRM?