Music giant EMI this morning announced that it would be releasing its entire catalog without digital rights management (DRM) restrictions, the first of the four largest music companies to do so. In addition, EMI announced that Apple's iTunes would be the first online music service to sell these unrestricted files starting in May.

EMI's move is dramatic. Currently, almost all commercial digital content sold online is constrained by DRM technologies, many of which are quite onerous and difficult to work around. Under the new plan, EMI will continue to sell DRM-restricted content itself and via various online services. But for those customers that are interested in DRM-free offerings, EMI will offer a logical and desirable alternative.

EMI announced that Apple will be the first EMI partner to sell both the old DRM-restricted songs and the newer, DRM-free songs side-by-side. Apple CEO Steve Jobs said Monday that the DRM-free versions of individual songs will offer twice the quality of the DRM-restricted versions, meaning that they will be encoded using the 256 Kbps AAC audio format, compared to 128 Kbps for the original versions. (In a bit of showmanship, Jobs claimed that the 128 Kbps files already offered "the best audio quality" offered by any mainstream digital music service, which is demonstrably untrue: All Windows Media-based online services already offer dramatically higher quality music files than does Apple.) The new songs will cost $1.29 in the US, compared to 99 cents for the restricted versions.

In a nice nod toward users, Apple will also allow its customers to upgrade any existing EMI song purchases to the new unrestricted format for 30 cents per song. This process can be automated so that, as songs become available in the new format over time, their libraries will automatically be updated. Apple will continue to offer both the 99 cent and $1.29 versions of songs, side-by-side, so that users can choose the format they want. A setting in its iTunes software will establish the default format users desire.

As for albums, at least for now, Apple will offer DRM-restricted and DRM-free versions of albums for the same price (typically $9.99). The new songs and albums will go on sale, worldwide, in May, Apple says.

One key piece missing from the deal is the long-awaited catalog from musical legends "The Beatles." Rumors have been circulating for months that The Beatles' catalog would be placed on iTunes and other online music services, and the recent settlement between Apple and Apple Corps. (which represents The Beatles and controls their catalog) would lead to that release. Apple is also rumored to be developing a special Beatles-themed "Yellow Submarine" iPod that would be sold with the entire Beatles catalog pre-loaded. On Monday, there was no news about The Beatles per se, though EMI CEO Eric Nicoli said they were working on getting that catalog online.