iPod touch plus WiFi plus FaceTime equals a mass market carrier independent videophone. Add Skype to that mixture and you’ve got a global communications device. I believe you can initiate a FaceTime session with just an email address, which is something almost everyone has.
The best thing about the potential of the iPod touch as a communications device is not having to pay monthly fees to a carrier like AT&T or Verizon. The second best part about a carrier-free global phone is that the state and federal governments don’t get to tax me on every single call I make.