Even Brown couldn't have believed they'd win but, surprise or not, the scale of the defeat will have piled on the misery surrounding Downing Street very nicely.
http://news.bbc.co.uk/1/hi/uk_politics/8167922.stm
Just looking at the statistics as compared with 2005, if my arithmetic is correct it appears that Brown's cronies saw their vote drop by c. 70%, the Lib Dems by 37% and the Tories by c. 13% whilst the actual turnout was down by c. 25%. I reckon Brown will be in denial, Cameron will be pleasantly surprised and Clegg will be wondering what he needs to do for the Lib Dems to be taken seriously ...