Ben Long has written a comparison review of Canon EOS 30D and Nikon D200. Here’s his verdict;
“Your price concerns might be a little clearer and easier to understand: the D200 costs more. The typical street price difference is about $300, so if you’re already feeling like the Canon camera is pushing your budget, the Nikon offering is probably not an option. Bear in mind also that you’re going to want to buy some lenses, so the $300 difference might impact your lens-buying options. On the other hand, you get a couple of features in the D200 that the 30D doesn’t have – such as the built-in intervalometer and better auto-bracketing – so there is a slight value add for the extra price of the Nikon.
If you make your living shooting in low-light, then I would say that you’re better off with the 30D. The better low-light autofocusing, and quality advantage that it has in low-light, high ISO situations will serve you better.”