The Daily Mail has slightly confused it - it's not known for being good on technology.
First, it's only a probe by the Competition Commission, and the parties involved have two months to reply. Don't hold your breath on anything happening soon; and the 12p less is an extrapolation of the French/German charge.
On the "iTunes is not just for iPods", bear in mind that even the DRM-free version of tracks to be sold through the iTMS (for an additional 20p) will still be in AAC. That format plays on some phones, the Zune and the iPod, but not on a lot of other mp3 players.