Macworld has a great article up today about the arrival of Skype on the iPhone (and soon the BlackBerry) and what the widespread availability of VoIP (voice over IP) clients -- which eschew the traditional phone lines to send talk via data instead -- means for cell providers like AT&T, Verizon, O2, Rogers, etc. who've made tons of traditional money billing us all by the minute.
One common future seen for cell companies is that of "dumb pipes" -- like DSL or cable companies that provide bandwidth but few if any premium services. Verizon shows how far (and foolish) they'll go to avoid that fate: