I would say the best keeper in the World for me is Gianluigi Buffon.
For many years he has been absolutely fantastic, it’s rare for a keeper to establish himself as a first team player so young and to maintain his fantastic form for so many years is amazing.
Iker Casillas would be a close second for me, again he has been at the top of his game for so long and it’s extremely impressive that he has been one of the constants of the Real Madrid team over the years when so many people have come and gone in the Galacticos era. Iker and Raul are proof that youth systems can provide great results even when the teams play at such a high level.
If Petr Cech hadn’t had the awful head injury, my list may be a little different. He is still good but before his injury you could have said he was unbeatable.
One to watch out for in the future Igor Akinfeev, he looks very promising and for me heralds a generation of eastern European players who will dominate the modern game. You just have to look at the impact Arshavin is having at Arsenal just now.