Exit polls numbers have dominated the coverage of the election up until now, and it's no wonder. It satiates our desire to get some metric of progress, and it helps fill the dead airtime between the polls closing and actual results.
But one can't help but think back to a mere seven months ago when exit polls confidently predicted a John Kerry victory in the United States. So it's important to remember that, ultimately, an exit poll is just that - a poll, with statistical margin of errors or worse - structural errors. And given that key marginals can swing on the basis of hundreds or even dozens of votes, it should go without saying that results can vary markedly from the early predictions.
There is precedent - the 1992 results were spectacularly wrong, predicting a 4.5 percent victory for the Conservatives. As a matter of fact, the Tories got 7.5 percent. So while exit polling for British elections has generally been very good, it hasn't been infallible. We'll still have to stay up to get final results.
