So, let's say that wifi or the equivalent DOES become available everywhere? Those of you who who don't want the tablet to have a phone will quickly delete Skype and breathe a sigh of relief, joyful that you got rid of the phone aspect of the tablet? Amazing.
The addition of a cellular adds a significant layer to selling the IT in an open capacity because of patent and proprietary issues related to the cellular infrastructure that in place differently in many regions. The cost to making it this open is not yet worth it (see Xohm/Sprint/Clearwire issues for proof of this).