Google has been expected, for a long time, to placate various Big Media companies about copyrighted video appearing on You Tube.

Everyone (including Google) wants some form of content filtering to be attached to You Tube, to prevent unauthorised bits of hit TV shows from appearing there. Today, we find out that Google will bring in a 3rd party, Audible Magic to begin this filtering process.

There’s a big debate about whether this is a stop-gap before they roll out something of their own, or whether something has gone awry with their own plans. Media executives are certainly getting tired of waiting for the promised filters.

I’ll tell you why it’s taken Google so long to implement anything at all. Because content filtering is actually pretty difficult. I would go so far to say that on this scale, it’s impossible.

Why? Because to know what to disallow, Google needs to have a copy of the content to compare uploads with. That means to be an effective filter of content, Google needs to have a copy of every TV programme ever made!

That’s not going to happen. But think how well that goal fits in with Google’s aim to organise the world’s information. Google would love to be the authoritative repository of the world’s television.