The first exit poll suggests there's going to be a hung parliament. What does that mean? It means that while the toff-ish Conservatives might win more votes than any other party, they won't have a majority, and they'll struggle to win any votes in the house. Here's a good explanation at the BBC's website.

Here's Jonathan Friedland at The Guardian with a nice little piece about watching BBC presenter David Dimbleby present the first exit poll. Dimbleby is like royalty in the UK. I mean, he's the voice of God.

For the political tribe, primitive in their ways, the moment on election night when the clock strikes 10 is one of urgent, almost physical intensity. They watch as the tribal high priest — David Dimbleby — holds up the numbers of the exit poll, as if displaying the entrails of a freshly slaughtered goat. The tribesmen — the politicians and those who follow them — gather round to stare, analyse and interpret.

California governor Arnold Schwarzenegger Tweeted: "Just called David Cameron to congratulate him on the victory. Even though the results aren't in, we know the Conservatives had a great day."