Buffon was in god mode in the first few months for Juventus till he got injured. From, then on he has has been injury prone. To label a world class player who hasn't been able to perform his best due to injuries is appalling.
Mate, there are many excuses for past greats like Ronaldinho, Del Piero, Raul etc. including Buffon. It happens you know... the world's best players can turn into very average players. Buffon has nothing to back up the claims that he is in top 10 keepers in the past year. In fact, he wasn't on the radar after Juventus was sent to Serie B. I specifically watched Juventus games to see if this guy is as faultless as they claim.
The fact that teams like Barca are watched and Valdes's every single mistake gets highlighted is really really unfair. Buffon makes plenty of them, and Italian media not concentrating on it doesn't mean it doesn't happen. It has been very quick that Cech fallen of the grace for 3-4 mistakes. And rightly so. But Buffon has been worse than Cech for 3-4 years now, IMO.
And besides injuries and generally being average, I wouldn't swap Valdes for Buffon because Valdes is younger.
PS
http://www.youtube.com/v/nMVLQSFgK-M&hl=en_US&fs=1&Look at the first Genoa goal. Its basically a pass to a near post and Buffon just sat on his ass. Second goal is even worse, he basically gifted that cross to an incoming player to tap in. A performance like this from Valdes would be enough for people to go on for about a year saying how shit Valdes is and that he is the weak link in Barca. It might be true given Barca has a cracking squad right now, but it is also unfair. People like Buffon and Casillas have been piss poor in past year or even more, but ask any fan to make top 3-5 keepers in the world, and 90%+ of case either one of those will be heading the list.
Here's highlights of Ajax-Juventus game.
http://www.youtube.com/v/FTk0Wspt1Y0&hl=en_US&fs=1&Watch the first goal. Valdes would be crucified for that. And these are the only two matches I watched carefully. If I wanted to find his more errors, I can just go through the goals that Juventus conceded in past two seasons. I am confident there are plenty of them.