Or, the next gen iPhone could just have gprs and expose that to javascript. In which case webapps could have all sorts of functionality included.
I hope the carriers eventually allow full IP access without extra extra charges, but I don't think they're ever going to give up the text messaging revenue stream. It's a tough problem, because they don't want to have to compete with VoIP providers on their own cellular networks.
And eventually we'll have the new network on the old TV frequencies that's open.