Sony Ericsson has confirmed that it is launching its own unlimited music service to rival Nokia’s recently-announced “Comes with Music.” Dubbed PlayNow Plus, the new service will be powered by British music-download firm Omnifone, and will feature music from all four of the largest recording labels.

PlayNow Plus is due to hit Sweden first, sometime in the final quarter of 2008, followed by the UK in early 2009 – US availability (if at all) was not revealed. A special edition of the forthcoming Sony Ericsson W902 will be the first phone released integrated with the service, which gives customers unlimited access to millions of DRM-wrapped tracks for one flat rate, plus the option to keep 300 tracks free of copy protection mechanisms when their subscription expires.

Aside from the music itself, PlayNow Plus will also include the ability to recommend albums or playlists to fellow users and search their recommendations. The music service is expected to cost 99 Swedish kronor, or $15, per month and users must sign a two-year contract. By comparison, the cost of Nokia’s “Comes with Music” will be bundled into the price of the handset and users will get to keep all of the songs they’ve downloaded after their subscription expires.