"Google's project for TV search is ultra-secretive; only a handful of broadcast executives have seen it demonstrated so far. To build the service, the company is recording live TV shows and indexing the related closed-caption text of the programming. It uses the text to identify themes, concepts and relevant keywords for video so they can be triggers for searching."
You need to do a bit of work to get an invite to Google TV.
Others are arguing it is an elaborate prank played by few people.
Whatever it is, the telvision entertainment is a huge market which awaits the discovery. Already, most of the Youtube and Google videos upploaded by the users contain television programmes.
Imagine the possibility of searching any TV programme ever broadcast on a TV channel. You can watch them on demand or buy them. Even, if you pay for some of them - people wont mind.
I hope Google is moving in the right direction to make Google TV as successful as Google Books.