I have a D5000 ... and wished I had bought the D90 when I first got into photography. So, with your choice: the biggest difference is the change from cropped frame to full frame. I think that going to full frame will be a better choice than upgrading to more pixels. The sensors on the full frame cameras are by nature better, that is why you do not need to get crazy with hyper-pixels on those cams. Pixels are only important if you want to print very large format. One thing the D7000 has over the D700 is the ISO range. I have not read any comparison as far as quality is concerned, but that would be something to consider. The D700 has better functions when it comes to flash photography ... I dunno, I was tempted to go for a used D2X ... for the full frame alone.