Harmonix has confirmed that the Rock Band Network will be opening up for beta access imminently. As previously reported on Pocket-lint, the service offers anyone the chance to upload music that they've created and make it purchasable in the Xbox 360 edition of the massively popular band simulator game.

All you'll need to do is create a MIDI representation of the song, record it to an acceptable quality level and then submit it for peer review by other users of the service. If it's judged as good enough, then you'll be able to pick a price point (from $1 to $3) and it'll then be available to the 13 million people who've bought the game.

Well, the section of the 13 million with Xbox 360 copies of the game, who've hooked up their console to the web, and who can be bothered to sift through the mountain of unsigned bands that'll inevitably jump on the service and find the good stuff.

A few companies have sprung up to offer the service to bands without the technical know-how to create the songs themselves. Pricing is pretty steep though, ranging from $999 for a whole track to $500 per minute in different places.

Still, a few larger bands and labels have already expressed interest. Jonathan Coulton, The Shins, Ministry, Evanescense, The Stills, Creed and All That Remains have been named by Harmonix, and indie label Sub Pop has said that it's going to release all songs and albums on their label to the network, including work by Nirvana, Sleater-Kinney, Flight of the Conchords and the Postal Service.

Harmonix says the store won't be enabled within the game "until we accrue a good base of content", so if that's not a motivation to get the band back together and buy a MIDI keyboard, then we don't know what is. We'll keep you posted.