I know I can't call the guy a "friend" because he shoots Canon, but yes.. he has waged war and threatened the status of our 24-70G mid range zoom!
He proposes his Canon 24-70L 2.8 is similar if not equal in terms of performance to our great 24-70G and hes willing to fight tooth and nail to prove this. Of course we all know the Nikon version will slaughter this Canon's poor excuse for a "L" lens.
From what I've seen, the Nikon G version of this lens is bloody sharp from end to end, however, there has never been a well documented comparison between these two monsters.
Of course, this test will have a lot of variable that will arguably skew the results such as: shooting from different bodies (5dmkII and d3s), Megapixel count, etc, but, he waged war first so I give him what he wants.
In your opinion, do you expect noticeable differences between the two zooms? From what I've heard, the canon lens is a tad softer at the 50-70mm end when shot open wide, however, none of those Canon fan boys will ever admit to this (maybe because they haven't dared touch a nikon lens before...)
Any other suggestions on how to humiliate this guy?
*Disclaimer: I am not a Canon hater, most of this is just for humor :) LONG LIVE NIKON!