Pocket-lint can reveal that in the UK the number of tracks users will be able to keep with Sony Ericsson's PlayNow service is 300.

Sony Ericsson's just-announced unlimited music service PlayNow will be powered by Omnifone, the company behind Vodafone's weekly subscription music service in the UK.

Due to debut with Telenor in Sweden later this year, PlayNow from Sony Ericsson will give owners of PlayNow-enabled "Plus" handsets access to a "vast" library of on-demand music.

Unlike Nokia's rival "Comes With Music" offering, music will be available from the big four record labels - Universal Music Group, Sony BMG, EMI, Warner Music Group as well as leading independents.

The PlayNow mobiles will come bundled with up to 1000 pre-loaded tracks at purchase and, at the end of the initial subscription period, will let consumers to keep those 300 DRM-free tracks under the "KYF" (Keep Your Favourites) plan.