Definitely buying one
I'm definitely buying the iPT5. Its a stellar upgrade from the iPT4. I'm one of those people who has no need or desire for a two year voice/data contract, so the iPT5 is exactly what I need. It does practically everything that the iPhone can do, but without the two year $2,500 voice/data contract that the iPhone requires.
In my case, I have access to wifi practically all the time so buying a voice/data plan is just wasteful and I simply can't justify the $2,500 it would cost over two years. In addition, I don't talk much on the phone when I'm away from home or the office.
On the rare occasion that I do need to make a phone call when I'm away from home or the office, I have configured a VoIP SIP application (Acrobits [$6.99], Bria [$7.99], 3CX [free], or Media5fone [free]) on the iPT so that its linked to my home VoIP service. Basically, I can use the iPT to place outbound phone calls (originating from my home phone number) from anywhere there is wifi. I can also answer all inbound calls to my home phone number on the iPT.
This powerful pocket computer is hardly a kid's toy.