Canon cameras, and lenses, cost less than Nikons.

Canon has a much broader selection of lenses.

Canon and Nikon lenses are of similar quality.

Nikon has way better exposure metering, and better flash metering.

Canon bodies are much better at high ISO (eg. 800, 1600, 3200) than are Nikon bodies -- important for night shots and indoor shots from a distance (eg. dancers).

Nikon lenses give you a choice of bodies from Nikon, Fujitsu, and Kodak. Canon lenses give you a choice of bodies from Canon and Kodak only.

The Canon 10D is the best all-around DSLR out there right now (no, I don't have one). The new Nikon D70 looks very good on paper -- but so did the D100 and it turned out to not be so good. .

Cheers