Is Federer the greatest male player of tennis?

Roger Federer has just won his 15 grand slam title, breaking Sampras's record of 14. He has also become number 1 again, overtaking Nadal. This has never been done before. He has won all 4 grand slams but not in the same calender year. But Nadal's absence through injury from Wimbledon and his injury at Paris would surely have helped Federer's chances.
Federer's win over Roddick at Wimbledon was a bit of luck, given the 5th set went to 16/14. He never broke Roddick's serve until that last game.

Sampras agrees he's the best player ever, but don't we have to take the different equipment and times into account. I'm thinking of Rod Laver here. He was off the amateur tour until all tennis became professional, so his wins in professional tennis at that time were not recorded. Laver and the other Australians of the time has 6 week boat trips to England to get there to Wimbledon.

So I think there are still questions about Federer's greatness. He has to win when Nadal is in the tournament and he has to win a few more grand slams to equal out the disadvantages of those who played in the past had.