For many professional photographers, their camera is a friend, a trusted companion and colleague. When an important story hinges on the functioning of their "partner," they want a product that is, above all, trustworthy.
As a result, photographers are often loyal to their chosen brand. Even if a shooter doesn't care for the ongoing Canon vs. Nikon rivalry — a conflict between fans of the two leading manufacturers of single-lens reflex (SLR) cameras that is akin to the zealous debates over the virtues of Mac and Windows — changing allegiances is tricky once you're used to the ergonomics of a certain brand and using its software, batteries and lenses.
This is all about to get much more complicated. Nikon is trying to up the stakes with the launch of its new D3 camera, believing that loyal "Canonistas" will suddenly want to pick up Nikon's ambitious new product in place of its direct competitor, Canon's EOS-1DS Mark III.