I have one.
It is a mediocre optical performer, which means it is no better than the
equivalent lenses from Sigma or Tamron.
The VR works quite well and once you use it you will not want to go back to
non image stabilized lenses.
18-200s are excellent travel lenses. I am dragging two of them (on two
cameras to be used by two people) to Africa this week.
My wife gets the VR, I get the non VR Sigma 18-200.
In my experience the 18-200s are far better performers than the budget
55-200s in that zoom range, particularly the execrable non VR Nikon 55-200,
the only lens I ever returned because it was too awful in every respect to
keep.
I would strongly recommend you check out the new Sigma 18-200 OS. My non-OS
Sigma 18-200 seems to have slightly less distortion at 18mm than my Nikon
18-200 and sure weighs alot less--weight and heft are the downside of
putting VR/OS in the lens instead of the camera where it belongs. The new
Sigma OS is supposed to be a different optical formulation than the non OS.
To be honest, had the Sigma OS been available 6 months ago I would have
bought it rather than the Nikon: I personally have found  no added value to
the approximately $2-300 greater cost of the Nikon.