15 MP and 6 FPS APS-C mode - definitely adequate for birds/wildlife, then coupled with multiple cross-type AF points at f/8, a wash with the 7D? A lot more resolution than the 5DII, ISO range equal to the 5DII, remains to be seen if ISO noise and DR follow the Nikon pattern of being better than Canon, but if ISO 3200 has the same noise at 36 MP as the 5DII at 21 MP, it's a win for Nikon.

I wasn't particularly interested in a 1D IV, because the APS-H sensor is not the sort of compromise between FF and APS-C that I am looking for. OTOH, a high-res FF sensor coupled with good AF and a decent frame rate - that's my ideal compromise between the two. To me, it seems that the D800 would successfully replace both my 5DII and 7D, and do it for less money.

@Rocco - you may be falling into the common trap of looking at images at 100% for comparison. That's why lots of people complain that their new 7D sucks because it's so much noisier than their old 40D. An 18 MP image from the 7D does look noisier than the 40D's 10 MP image when both are viewed at 100% - you're viewing a much smaller area of the 7D's image. To compare fairly, downsample the higher res image - the 18 MP image, downsampled to 10 MP, looks cleaner than the 40D. So...what does a 36 MP D800 image downsampled to 21 MP look like?

Those were my subsequent thoughts. My first thought? Honestly...a bit of remorse that my thousands of dollars worth of Canon lenses won't work with the D800.