I was looking for a lens that I could keep on my camera all day long, with a 28mm equivalent wide angle and a bit of tele, and most importantly: vibration reduction. Basically, I wanted the equivalent lens on the D40 that I had previously on my compact big zoom camera.
My first thought was to save up and get the Nikkor 18-200mm VR lens. That lens has a really useful focal length range and is quite expensive. Unfortunately, when I tried it on my D40 at a camera shop, I found that it was very front heavy on the D40. It threw the balance of the camera completely off.
Then I started looking at the 18-55 VR and 18-105 VR. The 18-105 was only a bit more expensive than the 18-55 VR. Trying it out at the camera shop, the size and weight was a good match for the Nikon D40. Definitely much more substantial than the kit lens, but nicely balanced. The zoom range gives the equivalent of 27mm to 157mm. In the time that I was looking for the new lens, I spent a lot of time with the 18-55 (non-VR) kit lens and found that I did not miss the tele end that much. The reduced tele compared to the 18-200 was obvious, but with the affordable price, I was sold.