Yes, PSP is said to be able to be used as a WiFi controller for PS3 and will provide new features such as the ability to save PS3 Saves to PSP vice versa.

It may also enable the playback of UMD Movies onto PS3, there’s even the silly theory of PSP becoming capable of a TV remote since they both have IR Ports; so it may even come true The main disadvantage in this case would be power as PSP can contain only a few hours use if not on AC adapter, whilst the PS3 and its lowers last quite a long time.

Extending on the saves feature, both PS3 and PSP will have Memory Sticks instead of Memory Cards; so that makes the memory more safe as it won’t stick out as it does now with the PS2

This also opens the fact that PS3 will also obtain PSP’s current features like Movies and Pictures which can be transferred between both of them