Firstly, it's not coveted by professionals. 😉
Secondly, you're also not always going to get the results you want from this lens. Like any lens with a wide focal range like this starting from 18 mm or therabouts, there's distortion on both sides ---- I'm talking barrel and pin distortion. It's not a fast enough lens to freeze motion (ie: to take a sharp photo of a moving object), and because of it's rather small aperture, it wouldn't be great for portraits. If you just want to take general photos of stuff while walking around, then it's a great lens. If you're not always going to be taking photos of family, friends, coworkers, the building across the street, random stuff sitting on your table, etc, then there are going to be many times when you want something that blurs the background while keeping the subject/person in focus, for example. This is why it would also be a good idea to own a lens like an 18-55 mm f/2.8 or something as a general walk-around lens. Hell, what about in low light situations? The VR helps, but a faster aperture is better. VR also won't help if the subject is moving, only when your own hands are moving/shaking.
Also, I wouldn't spend so much money on a lens that can't be used on a DSLR with a full frame sensor (ie: equivalent in size to 35 mm film). I know Nikon doesn't have any full frame cameras right now, but one day they might, and that 18-200 mm DX lens won't be usable. All the lenses I buy (except the Tokina 12-24 mm) can fit on cameras that have either an APS-C sized sensor like in the Nikon D50/D70s/D80/D200/etc, OR a camera with a 35 mm equivalent "full frame" sensor. Hell, those would work on film cameras as well.