Well, the absence of comments might mean that people who have a D3x (like me), are happy with it... At first there was a general "bashing" on this model because of it's price, so maybe those who could have one didn't go boasting on forums and kept the habit Then, others, here and there, argued about it's great color quality and IQ and of course the higher MP count countered by the ISO "ceiling" and the lack of video. Labelled as "studio" camera vs the photojournalist D3s, this debate is now shifted to the D800/D4 newer models !
My own impression is that bought that camera because I felt it was the last without video (I was right on that point), I "knew" it would be a sort of "niche" camera, but had everything I needed, as I do photography for my pleasure, high ISO (while nice) isn't so important as I seldom use long lenses, nor shoot definite action (sports and such)... I feel that you can go further then 1600 (2400) if you meter right in the camera !
Before, I took the D700 everywhere, now it's the D3x, it's just a bit bulkier and about the same perceived weight. As in all cameras it's the lenses that makes the difference in bulkiness, weight, aggressiveness, I use mostly a few primes and a small zoom and my pictures can be seen in my Flickr gallery in my signature line
I used to have a FM2n, even a M6 or a Bronica SQ, and with the D3x haven't yet felt that it induced a difference in my way of taking pictures (whether good or bad ), apart from having cleaner pictures and a bit of cropping elbow space !!!
Will I keep it for "life" ? Surely not ! But the D4, as the D800 aren't compelling enough for me to change, yet ! Maybe next generation