i've been spoiled by kawa kamera (which is a d700 and 35 1.4g). the lens is fantastic, and the nikon pro am FX series is just a joy to use. that said, it's big and heavy. but, it fits. dunno. the d700 and d800 are just the only bodies that feel right to me now.
once you spend enough time with a camera you and the camera become a bit more of a unit than you or the camera alone. having an slr with a single "walkaround" lens makes this even more natural. you can see and frame your shots, and know via muscle memory what you may need to flip to get it all right in that one second you'll have to make the capture.
the cool thing is that it doesn't matter what camera you become one with. it's a zen thing that applies to all reasonably well designed imaging tools. your brain adapts to seeing through the lens, your hands adapt to the controls, and the only thing you have to consciously think about is where you are and what you're seeing. to be fair, i went through a series of nikon bodies and rejected a bunch before i got here, but once i did, i started to see what thom hogan refers to as something silly like "unconscious precomputation" or "previewing the image in your head" or some such. i intuitively know silly things like the amount of dynamic range at different light levels and have completely internalized both the frame and DOF of my lens, as well as distortion and acuity properties across the frame.
and it's not a function of the camera or lens. it's just your brain getting really used to using a tool. i've had my body for 5 or 6 years now, and i didn't even get the zen bit until at least 2-3 years in. dunno. cameras dude. they're like keyboards but every time you click the button you get 10k words instead of a single letter.
+1 ^ to this. I agree that a 35mm (or 50mm) prime lens is probably the best walking around lens, instead of e.g., a telephoto lens, because the prime lens makes you move around more and think more about composing a shot.
As for the d800, I would love to have one. Or better yet a Nikon d800e. But right now my budget only went so far as the lowly d7100. Maybe next year, I'll move up.
