Bon - I just read on DP Review that the D5000 does *not* have an in-body focus motor...therefore, similar to the D40/60, you're limited in lens choices. That's a bummer.
Let me explain more....
When I had my D40, I wanted to use the $100 Nikkor 50mm SO badly...but it won't auto focus on the D40 bc the D40 requires lenses that have their *own* focus motor to auto focus (you can, however, manually focus). So, for me to use a Prime lens that
would auto focus on my D40, I had to go to a Sigma 30mm and the lens was about $460. This lens had its own focus motor though....
See what I mean about limitations? To some, that's no big deal though....