Re: What if it was not one of the top 4?
It almost certainly WILL be one of the top 4 (in order of likelihood, Federer, Murray, Djokovic, Nadal), but if not, the next most likely winners are Berdych, Soderling, Roddick, with Davydenko, Nalbandian, Baghdatis the best outside bets. Fish & Gulbis will do some damage but won't win.
"There is no such thing as 'the world'." - Enoch Powell.