Television continues its migration to the Internet, and big U.S. cable companies, like Comcast, are scrambling to make sure they don’t get left behind. Comcast recently launched an ‘Interactive Media’ arm and online site called Fancast, which looks a lot like the popular, free TV website, Hulu.com. It plans to build on this with a premium service for its regular, paying subscribers. Next up: interactive commercials, social networking, and television-based operating systems that make TVs look and feel a lot more like the Internet than the old idiot box. The goal? Stop free content from ending up on the web before it’s too late.