With reference to TV commercials for the late local news, it's a sarcastic phrase written in newsgroups or chat rooms in reaction to an overwrought argument.
For example, "Imminent death of the Net predicted. Film at 11." The phrase has also become a funny kind of "cop out" at the end of a news article or explanation, as if to say, "it's too early to draw any conclusions that you'll hold me to later" (when the author may not know where a particular technology is headed). He or she is signifying that the debate will continue to rage on. For example, "A hot topic is the future of e-commerce and the B2B sector. Film at 11." Quite simply, it means there's more to come.