AT&T Wireless Pulls Back on Push-to-Talk

Industry observers say the early walkie-talkie efforts from Sprint (FON Quote) and Verizon (VZ Quote) have done little more than validate Nextel's technological superiority.

"They can't build a better mousetrap or differentiated push-to-talk service," says Dunsby. "So the best thing Nextel's challengers can hope for is building their own interoperable walkie-talkie systems to help boost revenue."

But don't expect any help yet from Nextel on compatibility, says Yankee's Entner. Even though the Justice Department is reviewing the push-to-talk business, industry experts say there's no rule that says Nextel must open its system to rivals.

"It wouldn't be smart, financially, for Nextel to be interoperable with other carriers until they have five or six million push-to-talk users," says Entner.

Hand it to AT&T Wireless -- they know when to call it quits.