Since Skip said to start this discussion here, I can't help but obey. 
In this corner, weighing in at 30.3 ounces, known to everyone as the "High ISO Heavy Hitter", the Canon 5D Mark 3!
(the crowd cheers)
And in that corner, weighing in at 31.7 ounces, known to everyone as the "Megapixel Muscle Machine", the Nikon D800!
(the crowd boos, and many vegetables are thrown)
May the best camera win!
*DING DING*




