I've been wondering about an August 09 general election as well - my suspicion is Brown suddenly looking like a hero off the back of an 'Obama Bounce' in consumer and market confidence in the early part of the year, and thus chancing his arm.

I actually think he might win as well, Cameron has hardly made a great impression, and if you take away the "arrgh, recession, not Brown" factor (which the apparent "success" of Brownite fiscal policy worldwide could well do) he's not looking like a winner.