I've had decent results out of my kit lens (18-55) with my D40. You're right it's not a pro lens by any stretch of the imagination but for the majority of people it does a good enough job and is way above your standard point and shoot camera. Most 2.8 lenses cost more money than a lot of people's bows/guns and we all know where our priorities lay when it comes right down to it. That 70-200 2.8 VR you have is on my list for sure, but for now I'll have to settle for my 55-200 4-5.6 VR.

This is from my D40 with the 18-55 kit lens. Sunet in Juneau, Alaska this past August.



And one with my 55-200 4-5.6 VR maxed out @ 200mm