Yes, we've known about Skype coming to the PSP since February 2007 when we discovered a reference to a skype_plugin.rco in the PSP firmware. Nothing new. It's just officially being announced.

It's not a replacement for the tablet, that's for sure.

There is no mic on the PSP, not even on the PSP camera, so it will probably be coming with a headset.

Other functions that exist in the PSP firmware that are currently unused: G-Sensor (Sony Vaio hard drive protection), ATA hard drive functions and Bluetooth functionality.