Neur still lacks a lot of experience. He will definitely be the best in the world some day, but if you watch Bayern in the Bundes Liga you'll see the mistakes that he makes are often amateur mistakes. Casillas is one of the world's best shot-stoppers but he has never been, imo, one of the best keepers in the world. I mean that his reflexes are probably second to none, but his positioning has always been poor as well as his decision making. He isn't the best in the air either. As for Buffon, he was the best a few years back, there is no doubt in it, but last year he truly was not tested very much due to Juve's solid defense. In addition, the season before that he was out for for a long time because of injuries. He still has his moments of brilliance, but I'm not sure he is still in the top 3 keepers in the world, and this coming from a Juve fan. In terms of consistent world-class performances, in terms of big saves in big games, in terms of importance to the team, there is no doubt in my mind that Cech was the best keeper in the world last season.