Nikon Cameras:
Generally speaking, Nikon makes the best 35mm format cameras for professional photographers. Nikon cameras are generally more intuitive to use and they tend to be more ergonometric. They also have much better flash systems than Canon cameras. Furthermore, their high end lenses are simply second to none and the build quality of their cameras are excellent. Consequently, Nikon cameras tend to be great cameras for weddings and studio work. It is easy to understand why most professional photographers end up with Nikon. However, Nikon’s pro-consumer and consumer cameras are a different story.
Canon Cameras:
Several years ago, Avis ran a series of commercials touting that because they are number two, they try harder. Well, that certainly seems to be the situation for Canon. Canon’s intermediate and consumer systems tend to have better specs than Nikons. Furthermore, Canon is usually the first company to come out with new breakthrough technology. (Nikon typically follows, but often will best Canon’s attempt.)
Nikon vs. Canon:
Which Camera system is better? It really depends on far you want to take your photography. I have owned both Nikon and Canon digital SLR cameras. I was a loyal Canon user until Nikon introduced their 18-200 lens. This seemed like the perfect travel camera lens. Once I began using a Nikon D200 with the 18-200 lens, however, I began to appreciate the layout and features of the Nikon camera. If you want the best system out there, go with Nikon. However, you will be spending several thousand on a camera and be lugging around some very heavy glass (i.e., lenses). If you want a more manageable system that still takes great shots, go with Canon.
For point and shoot cameras, Canon is the clear cut winner. (Panasonic also makes great point and shoot cameras.)