Federer until 2010 atleast was very good. This nonsense of him being a crickety old man already at 26, is even more ridiculous than those who say Nadal is fading at 25 (keep in mind as we always reminded by ****s Nadal was an early bloomer, Federer was a super late bloomer which explains away all his defeats until turning 23). Federer from 2008-January 2010 reached the finals of 8 of 9 slams, winning 4 of them. In 2010 he won Australian Open, WTF, Cincinnati Masters, reached 2 other Masters finals, had match points to be in the U.S Open final.
He only faded slightly and the competition had gotten alot stronger than just facing Hewitt, Roddick, mid 30s Agassi, or sometimes Baghdatis, Gonzalez, washed up Philippoussis in virtually every Australian, Wimbledon, and U.S Open final. Instead the two pigeons Hewitt and Roddick were replaced with Nadal and Djokovic, needless to say an enormous upgrade, while the likes of regular top 5 and sometimes top 3 players of the Federer era such as Blake and Ljubicic were replaced by people like Murray and Soderling. This year, and starting last year after Australia, is the first time he truly regressed alot.
Federer wasn't a rickety old man in 2008, but he was declining a bit. I don't see what's the problem with this, 2004, 2005 and 2006 were years of extremely high play from Federer in which he won a hell of a lot, no way you can keep this up forever - in truth it's more a mental issue than a physical one. 2007 was a slight dip which continued in 2008. He was still very good, but against someone like Nadal who was himself improving a bit each year, Federer needed to be at his best or near enough. In 2007 Federer was near his best at Wimbledon (apart from a few mental cracks) and Nadal was not as confident as he was in 2008 - that's all it took for 2 years to produce different results) As Nadal got a fraction better, Federer got a fraction worse - still able to play well, but less consistant and more prone to lapses of concentration.
In terms of competition, guys like Hewitt, Roddick, Safin and Nalbandian get less credit than they deserve and might have won much more had Federer not destroyed them so often. Nadal, Djokovic, Del Potro, Murray are of course a step up (dunno if you can say this about Soderling) but firstly thay have responded to the level Federer was playing at (Djokovic has had to raise his game massively to topple Federer and Nadal - he wouldn't be playing this good without them as a benchmark).
Secondly if we look closely we actually see that Federer has had to play Djokovic in a slam more times than Nadal has, and has the same amount of wins over him as Nadal. Overall he has a slightly bigger lead over Djokovic in H2H than Nadal has. This year he's played him more in slams and desepite nearing the end of his career, he's beaten Djokovic in a slam this year where Nadal hasn't.
Federer has also played Del Potro more times in a slam and has a better H2H against him.
Federer also has not lost a set to Murray in slam meetings, Nadal has lost 2 matches to Murray in slams and their first match in a slam where Murray was pretty inexperienced went to 5 sets.
If we talk about Soderling, Federer has also has a 5-1 H2H in slams (16-1 overall) first of those slam meetings in 2008.
So it's not exactly as if Federer couldn't hold his own against these new guys because he's done pretty well even in the later stages of his career. The only one to give him big problems is Nadal. But most of these other new "strong" players he's faced as many times as Nadal has and done at least as well against them.
