NEW YORK (AdAge.com) -- Internet Protocol TV sites like Hulu, iTunes, Amazon Video and TV.com are rapidly evolving into a game-changing force for the television industry. Even before the recession forced growing numbers of consumers to cancel their cable TV subscriptions and explore online alternatives, this new trend was clear. At Ad Age's Digital Conference, Verizon CMO John Stratton was asked if this exploding new world of IP TV wasn't a serious threat to traditional subscription TV.