Apparently Boris Johnson had just one glass of champagne at his victory celebration, and spent most of the night with advisers planning his first hundred days. It's good that Johnson knows he has to hit the ground running, because being London Mayor from 2008-2012 is not going to be the simplest job in the world.

The new mayor has two major projects to oversee. The first is preparing for the 2012 London Olympics. The budget has already spiralled from £2.4bn to over £9bn, but officials are said to be working to a £12bn target.* Johnson will need to do everything he can to control spending and ensure that Londoners do not end up shouldering more of the burden than was originally agreed (£300m). He is also going to have to make sure that London's dodgy transport system is ready for the influx of visitors.

The second big project is Crossrail, the long-awaited train line linking Heathrow with the City and the Southeast, for which the Mayor has direct responsibility through Transport for London. Keeping Crossrail on time and on budget is going to be a major challenge.

Apart from good management, voters are going to want Johnson to deliver tangible benefits in their everyday lives. More police on the streets and a reduction in violent crime, so people feel safer. Less delays and disruption on the tube and less congestion on the roads, so people can get around more easily. More housing so that London life becomes a little more affordable.

All of this is possible with the right policies (and Johnson has some good ones) but it won't be easy – especially when the new Mayor's every move is going to be scrutinized by a hostile central government who would love to see him slip up. London is going to be seen as a testing ground for Conservative government, so the stakes are undeniably high.

* Is it too late to send it to Paris?