I don't know much about Canon DSLR's so please correct me if I'm wrong...but I thought some Canon models let you set "in camera" smaller sized Raw files, reduced from it's native resolution capture.Nope, RAW is RAW. JPEG lets you dial down.
What I don't understand is why Nikon doesn't implement the same thing. The D800 would greatly benefit being able to shoot 24 or 16MP or smaller Raw files "in camera" without the need to import 36MP files to one's computer and then set a PS action to reduce them.
This would save at the very least having to import 500-100 RAW full sized files from a given shoot if that size file is not needed...especially if one is on the road with a small laptop. Except for possibly the need for a larger/faster in-camera processor, I can't see why its not done or offered as an in-camera option.
Dave (D&A)