So who'll be running things later today?

Amidst all the discussion about the end of the "Blair era" and the beginning of the Brown era, one point that isn't too clear is who will be running the country from the moment Blair tenders his resignation to the Queen and when Gordon Brown "kisses hands". (Somehow I just can't imagine Brown on his knee kissing the Queen's hand! Yes I know it's not supposed to be literal but that hasn't stopped some ministers giving a kiss anyway.)

This is hardly unprecedented - there have been many times in history when there have been gaps of days if not weeks between on Prime Minister leaving office (or dying) and another being appointed. A convention long existed that when a Prime Minister tended their resignation the entire government left office immediately even though it could take more days before new ministers had been appointed.And the United Kingdom is not alone in this - in the United States it was never very clear until 1937 whether a President's term of office formally ended at midnight or noon (and there's a story of a hungover Senator being President for one day - see Wikipedia: David Rice Atchison). But the modern world expects so much more precision look at the way that both Ronald Reagan and George W. Bush took steps to ensure that Presidential power was temporarily transferred for a few hours to their Vice Presidents whilst they were undergoing operations.

For example if there's an attack on this country between Blair and Brown, who has the authority to respond? Does David Miliband still have authority to deal with the flood emergency? Or does the response have to wait until Brown has appointed an Environment Secretary. And for that matter when does the appointment take effect and empower the minister - an announcement by Brown? An announcement by the relevant Department? A formal appointments ceremony? Does anyone know?

Is this the best way to run a country in the 21st century? Is there a better way to do it?