D70 is basically an F100 with CCD instead of film. I find F100 to be the best camera out there (affordably professional). Also, you can mount any nikon lens in all its SLRs, including digital, as opposed to other cameras where there are different mount for digital and film. I think lens for nikon is cheaper than for cannon, because of many old auto focus lenses of the mid-90's. so, i would go for nikon (mostly because of personal experience with nikon). But for portability and cost saving matter, I would get a Nikon 8900 (same lenes and upto 10x (optical) ~= 300mm with 2x and 3x lens adapters. The only disadvantage of this is that you cannot get images using less than 24 mm, where as on SLR you can go upto 10mm.