Thanks, Brian and evryone. I'm not questioning the capabilities of the D5000. I've captured some great images with it. I'm almost certainly going to buy either the D7000 or the 17-55. I didn't mean to give the impression that I was not satisfied with my current body. I'm just considering an upgrade with either a new body or a new lens. So the question is not if I should buy, it is which would you buy? Thanks again to everyone who took the time to comment.