For my personal area network (PAN) (PDA, NIT, UMPC, Laptop, Phone, PMP, Camera(s)), wifi is already more than powerful and fast enough. In fact, to make it really PAN level, you could dramatically lower the power output of wifi.

1 gateway device with voice, messaging, and data capability to the outside world, acts as a wifi access point for your PAN, and has a SIP server for relaying voice calls for your other devices, and a jabber server for relaying messaging for your other devices ... is more than good enough for the hub of such a "specialized device" perspective.

Then you use an optimized video camera for taking videos, an optimized still camera for taking photographs, a PMP for your media playing, an laptop for mobile work, and a PDA or NIT or smartphone for your handheld computing and/or communications. And if any of the prospective mobile hard-drive makers* get off their butts and release one, you could even have a NAS type device in your PAN.


(* not those dorks who keep releasing "portable hard drives" that only have USB interfaces and no batteries, I'm talking about the ones who are looking at releasing Bluetooth FTP enabled storage devices with internal batteries; though, perhaps these days I'd prefer to see them use a wifi based storage protocol than Bluetooth)

The problem with the specialized device PAN model isn't the radio power problem. It's that no vendor has created an adequate gateway device. And marketing seems focused on heading toward convergence devices right now (which are the exact opposite philosophy from the specialized device PAN model).

I'm hoping someone will hack an android phone into being able to do the gateway functionality, so that it can evolve into satisfying both camps. Though, if Nokia ever gets off its butt and releases a Maemo phone, it could possibly function in that capacity as well.