The Nikon 18-200mm is quite an impressive lens given its vast zoom range. Revolutionary when initially launched, it is sharp at most apertures and focal lengths, gives you a nice bit of wide and a lot of telephoto. The only thing I don't like is that on the D90 it really is a bit heavy and large, and doesn't balance that well; though I am sure it would be better on a D300.
This leads me to the point of the new Nikon 18-300mm. Honestly I don't really get this lens. It is another 4cm longer than the already large 18-200mm and is even heavier. It also is another $200-$300 more. I rarely need more than 135mm on a DX camera (200mm on full frame), though I will say 200mm on DX is a nice occasional luxury, but not for the extra weight. For 300mm, as I use it so rarely, I might as well have a separate lens for occasional use, and not compromise my main lens. Interestingly, I sold all my lenses longer than 200mm a while ago, and now just use a 2x teleconverter on the Nikon 80-200mm f2.8.
|Nikon D90 with Nikkor 18-200mm|