AT&T is discontinuing its CallVantage "over the top" VoIP service, a move that has some observers calling AT&T stupid for turning its back on the future. But that isn't what AT&T is doing. It will focus on using VoIP as a key part of its triple-play or quadruple-play consumer offerings, instead of devoting resources to a small, if well-run service that offers little synergy or business value with the other things the company is doing.
It just makes more sense to focus on VoIP as a part of a bundle.