Erratic wb came from artificial lighting BUT my D300 never had such a problem. It'd get the WB wrong, but 2 shots wouldn't be different. Anyway, in natural light the wb is a tad off, either that or its the lcd but i'd prefer the wb to be properly reflected on the lcd because i shoot mainly jpeg, and i edit on the go (colour balance etc). So it's either the lcd hue or the wb, or both.
Anyway "understatement" or not, it's my opinion. I've been waiting to go to fx for a long time. Even when i got my D300 i wanted a D700 but couldnt afford it. I know the benefits of fx, its good to list them down because my opinion may not reflect how many other people feel about the camera. I expected to be blown away by the viewfinder, have to adjust to the fov, but i didn't. It felt like i owned the camera for a long time, an 85 was an 85, 24.. (okay i must admit the 24 was the only lens i felt was a bit strange..a bit wide), 50 a 50, 105 a 105, etc. And one of the perks of fx for me was the thinner dof appearance. Whatever you listed down were reasons i told myself were valid to move to fx. I just wasn't blown away. Maybe i've been looking at pictures by my lenses on fx online too much i'm so used to the fov. And maybe i don't appreciate the viewfinder cause i've never used the D300 and D800 side by side. But i've used the D300 for 3 years so i'm used to the dx viewfinder. I suppose it's just me. I'm not sure if i should take offense because you just made it seem like i moved to fx without knowing the benefits. Anyway i said subtle in every respect. Resolution wise if i used DX mode and cropped a bit more to get more "reach" in macro i'd end up with something along the D300's resolution. I enjoy the subtle benefits of the D800, except the grip, but major improvements to me are on paper and using it hands on wasn't as mind blowing as i expected.