Compared to the other 5 wins, this is the most difficult to pick because of the year that Roger has had, and because of the demolition in the RG final.
This is Wimbledon though, and Roger seems to be playing very well. Federer is unbeaten in 10 career grass court finals while Nadal is 1-2 in grass finals.
Federer hasn't had any real competition on grass this year. When you look at who he's had to play, the rankings are not impressive:
Halle -
Berrer, 91
Vacek, 342
Baghdatis, 25
Kiefer, 32
Kohlschreiber, 36
Wimbledon -
Hrbaty - 273
Soderling - 41
Gicquel - 53
Hewitt - 27
Ancic - 43
Safin - 75
He is yet to face a top 20 player on grass this year, so a two-time Wimbledon finalist, Queens champion, and world number 2, will be a real step up.
I still pick Roger.