Obviously it was a pretty devastating one for Federer fans. His capitulation in the fifth set was as inexplicable as it was lame. Crying during his speech didn't help either, it just made the difference between him and Nadal seem really big. Nadal has to keep trying to prop him up by telling him how great he is. For the rest of time (unless Federer wins the French open, preferably against Nadal, which won't happen) the Nadal issue will always prevent him from being considered the GOAT. Two comments about the final sum up a lot. Shelly (who I don't really know) said, "Nadal looks like he's trying to win and Federer's trying not to lose." I've thought this often when watching them play, but I never thought to put it so bluntly for some reason. Greg said something like, "this is especially bad because Federer really thought he was going to win." Which I also think has a lot of truth to it. The crying was a running out of excuses, there are always stories to explain away why things went the way they did, and I could tell a few myself, but this one was a little too much.
On the other hand, in a lot of ways it just shouldn't seem like such a big deal. The best player in the world beat the second best player in a close and, fifth set not included, good match, so what's the big deal? Getting to the final really is very good and it looked likely that he wouldn't even do that for a while. It's worth remembering that there is no precedent for someone going so deep into every major tournament he plays. All the other greats got beaten by random players in random matches. Federer only loses to Nadal, an all time great and in the final.