The Tories are thought to have paid about £50,000 for the main ad space on YouTube today. It may remind Conservative supporters to turn out (I'm always surprised at the number of people who say they simply forgot to vote), but I can't see it winning any converts, and it may even turn some against Cameron.
Once again, it seems that the Conservatives have confused form with function. Those who appreciate YouTube as a user-driven and interactive service aren't going to be impressed by the Tories' colonisation of the site.
Gordon Brown's remarkable speech to Citizens UK was a YouTube hit (125,000 views) because it was relatively short (ten minutes) and an unusually passionate and moving address.
If Cameron really wants to win over the "YouTube generation" he'd be better off making a few decent speeches, rather than using the old command-and-control method of buying ad space.