Be aware that although the Nikon D80 has less high ISO noise than the Nikon D200, no Nikons have as good as ISO performace as a canon 30D (ISO 800 - ISO 3200 range). This makes indoor action hard to shoot and get really clean shots. The noise removal in the D80 also removes a fair bit of detail so i probably wouldnt use it.

The metering, view finder, and flash sync is better on the nikon so its a pretty damn good trade off. If I wasnt going to buy top of the range canon L glass I would have bought nikon myself probably. The Nikkor ED 18-200mm f/3.5-5.6G IF DX VR would be teh first lens I would buy, but depends on your budget oh course. That lens is pretty much the best walkaround general purpose lens, it covers a awsome range.