So a few posts back I put "a new camera" on my list of things I wouldn't be getting anytime soon. Happily, due to a couple generous birthday cheques and mid-life crisis reasoning, I was able to get a new camera. (Plus my cousin Sheila recommended it as she has one as well and she has a lot of sway with me). I decided on the Nikon D7100 based on a few features it had a I really wanted and the reviews of it saying it was as close to full frame sensor you could get for the price. It does in fact seem to have all the same features as the 610 except for the full frame sensor.
Because I need to know I didn't waste 1 000$ I did a few tests to make sure there was a noticeable difference in the images.
Basic shot - D7100 is on right
I think the sharpness and colour show the purchase was an improvement
100% side by side - D7100 is on right
I was little disappointed there wasn't a bigger difference. The D5000 is 12 megapixels and the D7100 is 24. Maybe naively, I thought the new camera's images would be twice the size. There is a definite difference in the sharpness and clarity with the new camera though.
Differences I noticed right away
The D7100 is so much faster than the D5000 taking photos it took me a few days to adjust to it. The camera can also do 5 step bracketing over the normal 3 step which is a great help to me in some of my work. There seems to a be less noise in low light shooting and the controls are much better situated after you get used to using them for a while. I miss the graphic menu system in the sense the D5000 visually showed you how much the lens was open when changing the f-stop, I just like visual queues over numbers but the menu itself was a lot more easy to understand in the newer camera overall.