The depth at the very top of the game has definitely gone up, however it's also true that Nadal's rise to prominance for much of this year and the fact his game has developed and gone up a level in all facets, Fed had gone a bit stale somewhat and was unable to recapture his consistently brilliant form of previous years. Nadal was producing amazing stuff, but Fed wasn't quite himself.
Next year will be the acid test for Nadal. If Fed wins this slam it'll be a huge boost for his confidence which is already on the up again, he'll enter next yesr reinvigorated and with extra motivation, plus the likes of Djok and Murray will also be challenging at the tail end of slams. If Tsonga can recover well and the likes of Ferrer and Nalbandian find consistent form there'll be great competition and of couse there's the mercurial Marat.