...that all or almost all of the world leaders present at the G8 summit had something seriously wrong with them.

Putin is seriously dodgy.
George Dubya officially lost the election.
Berlusconi is a prime minister who owns much of the country's media.
Um... Blair's party only got 25% of the vote (the general public didn't vote for Blair himself at all).
Um.. not sure about the others but I'm sure most of them have less than 50% public support.