If I was a London Labour strategist I'd use the coronation of Gordon Brown as the beginning of a 100 day war leading into the annual Labour Conference before using the new leaders speech to call a snap election.
Politically it has a lot of advantages. It enables the new PM to launch a short term policy blitz with plenty of electoral sweeteners; it will catch the Tories unprepared - there is no way that they will have produced a coherent programme of government by the Autumn; and Brown will invariably be on a honeymoon.
The one major problem for Labour is that the bank is empty - £20m in the red. They haven't the war chest to match the Tories at present.
If they went early I think Labour could win an overall majority. If Brown decides to serve another two/three years, the Tories will overtake Labour. The question is will there be enough Lib Dems left in Parliament to make up the numbers for a Lib - Lab arrangement.
We live in interesting times as they say.