My sample is tack sharp. But the default in camera sharpening is on the soft side - 3 on a scale from 0 to 9 - in the sharpening menues. That is simply a matter of turning up the in camera sharpening. For my taste 9 is too much, but 5-6 works OK for me for most purposes, if I don't intend to PP apart from distorsion correction. If I expect to do PP later I will set the in camera sharpening more conservatively and then sharpen later, when the other tweaks have been done on the computer.
Before the D300 came out many people claimed that the 18-200 lens would be useless on the D300, because it wasn't as sharp as first rate primes and pro zooms. Well, with the D300 my 18-200 is considerably sharper than on my D100 that preceded it, though I can also see that the D300 has resolving capabilities beyond what the 18-200 can deliver. But I have to look at 100% or sometimes even 200% pics to see that at all. That goes for JPEGs out of the camera, whereas I used RAW exclusively on the D100. Carefully PPed RAWs out of the D300 may likely yield even better results, but I haven't done that much, because Capture NX works hopelessly slow on my computer (I used to use Bibble, but it haven't come with D300 support yet).
When talking about sharpness there is a delicate balance between sharpening and noise reduction. There are no hard and fast rules here, it's a matter of personal taste.