I received my D7000 about a week ago and I couldn't be happier.
after a couple of days of use, though, my kit lens started making a distinct, high pitch noise when AFing. sounds a bit like the metallic noise an old hamster wheel would make when rolling (sorry, I couldn't think of anything more appropriate than that . it's not loud, but quite noticeable. the focus speed and accuracy isn't affected (as far as I can tell), but I'm slightly worried that this might mean an early breakdown some time. I also bought a nikkor 10-24 which doesn't make this kind of sound.
I once had the same thing with my olympus 12-60, but then I'd also get really noticeable front focusing. I had it serviced and they replaced the focusing motor.
anyone else experiencing this? more importantly, should I send it in as soon as I can or should I just wait a couple more months to see if it gets better or worse(since I still have several months of warranty left)?