Its a pretty dope lens man, and it better be for what they go for. I found one that a guy had barely used for a few bills less than they normally go for, and even buying that killed my bank account. I'm only an amateur photog, so my review wouldn't be as technical as you'd get on sites like kenrockwell or dphoto.
Everyone says that if you can afford it, buy it and replace every other lens in your bag between 18-200. Nikon makes sooo many lens between this range, and they say that the 18-200 shoots just as well as all these other lens. Basically its a convenience luxury if you feel like you can afford it. Since you likely already have an 18-55, 18-70, or 18-135 lens, you'd have to get something like the 55-200 to have a telephoto in your bag. The 18-200 lets you do it all without having to take your lens off. Also, some will say that VR makes a big difference, and some say it doesn't. Its really all a matter of personal preference, how shaky your hands are, etc.... I'll get some shots up as soon as I find my camera cable.