Not impressed with D5200 samples at Imaging Resource

20% higher resolution does not automatialy imply better image quality.  There are other factors involved obviously.  8 MP DSLP will produce much better images than 16 MP point-and-shoot camera.

D7000 is a higher end camera than D5200 so there is no need to be surprised and "disappointed" by the results of your comparison.

I followed the link you included (I have never before heard of that site).... I was more surprised when I compared D7000 to the new Olympus OMD... While Nikon D7000 did have much better colour rendition, I found that OMD images were much sharper and showed more fine detail even though they were more closely croped (I could understand that either - you woould think that they would provide identical croping for comparison).  This is contrary to all the reviews and comparisons I have read on line while trying to decide between D7000 and OMD (I did get D7000 in the end).