Concrete details regarding Sony and BT's collaboration announced earlier in the year have emerged from the publisher's Games Convention press conference today.

Go!Messenger is a wireless communication package for PSP, due in January 2008, which utilises the latest IP technology to enable PSP owners to keep in touch with each other from any wireless broadband internet connection.

The service itself is free.

By downloading a small application provided as part of a future firmware upgrade (thought to be ver3.7), you'll be able to instant message each other when connected via Wi-Fi, using what Sony is describing as a "new and intuitive on-screen keyboard".

By adding a headset – a peripheral is expected to launch alongside the service – voice chat and voice messaging becomes possible, and by connecting Go!Cam, the optional PSP camera, you then also have the ability to make video calls to friends and leave video and voice messages.

Make sure you don't miss out on Sony's other GC PSP announcements: Go!Explore, Go! video download service and PSP Slim and Lite European release details.