We’re not quite sure what the point is either – the implementation isn’t that useful. PSP users will only be able to make calls using BT’s VoIP software through WiFi networks. At first users will only be able to call other PSP VoIP users and some BT lines, though eventually the hope is that they’ll be able to call any phone – like Skype has been doing for the past three years.
Though frankly, if the PSP can’t connect to a real cellular network and make genuine roaming calls, it’s nothing more than a fairly pointless novelty. If you really want a mobile phone that can make proper VoIP calls, you might want to look at one of Nokia’s smartphones instead of holding a bloody PSP to the side of your face.