EA has revealed a new social games service called Nucleus that it plans to implement into 25 titles by the end of 2009.

Nucleus will work in a similar to way Xbox Live or PSN, allowing you to share scores and challenge friends online, the only difference being that it will be cross-platform.

The publisher will start by implementing Nucleus in all its sports games, Spore and Battlefield Heroes, with the rest of the 25 following in due course.

Shawn Fanning, known from his fame with Napster, and whose company Rupture was recently bought out by EA, took to the stage to explain the Nucleus concept further at Monday's EA press conference at E3.

Basically, Nucleus will allow you to set challenges for friends. For example, Fanning said, you might tell someone they have to get their Warhammer Online character to level 30 and unlock all the Battlefield achievements by next weekend, and Nucleus would then also allow you to tell your mutual friends that you had set this challenge. Talk about pressure.

EA didn't specifically say which formats would be supported but we're going to hesitate a guess at the big three, with probably the PC thrown in as well

Expect to hear more about Nucleus soon.