At the CES show in Las Vegas, Sony has confirmed the rumours about PSP/Skype compatibility and that the service will be launched worldwide at the end of January.

The Skype service will enable you to make phone calls through your PSP using a headset - for free to other Skype users or for a fee to landline or mobile numbers. It will also feature an instant messenger client similar to MSN. Currently around 250 million people are Skype-registrated.

The service will only be compatible with the new PSP Slim & Light (or known as the PSP-2000) however, possibly because it requires the console's better Wi-Fi performance and additional RAM although Sony hasn't elaborated on why this might be.

A software update will also be required before PSP owners can start using Skype's features. This will add the Skype icon to the Network category in the home menu and allow those without a username to sign up for an account. Users will also need a wireless internet connection, a Skype-compatible audio input device and Memory Stick Duo. Then, whenever they are logged in, they'll be able to see which of their contacts is online and send and receive calls and messages.

To register for an optional SkypeIn number that lets users receive calls from landlines and mobiles anywhere in the world, a Skype credit card would need to be purchased. The costs of such calls are yet to be confirmed, but the regular prices listed on Skype's website work out at £10 for 13 hours of calls to landlines worldwide.

It's not yet clear how all of this will fit in with Sony's previously announced BT-partnered Go!Messenger service though. It's also meant to be launching in January 2008. Regardless, communication on the move - in the form of a free basic package - is another welcome feature for the console. We'll keep you posted on when the update becomes available.