I think you'll find them pretty much equivalent for all of those categories except sports. In the sports category I think you'll find that the more advanced AF system will be helpful, and if you have older lenses the 7000 has a focusing motor and is therefore compatible with pretty much all of the AF lenses ever made for Nikon. The 5100 requires newer lenses with focusing motors in the lenses.
_____ Brian... a bicoastal Nikonian and Team Member
My gallery is online. Comments and critique welcomed any time!
I love my D3200, the pictures and crop ability are great but I am in the same boat you are as to function. There are things I wish I could do but at an entry level camera are omitted. I'm hoping the pro level DX will be updated or the 7000 will be updated. I hate to give up my 24 meg pics now that I have gotten use to them!
In addition to the better AF system, the D7000 has a penta prism viewfinder compared to the penta mirror viewfinder in the D5100 and D3100. It also has a sub-command dial and more dedicated buttons to quickly change settings without goint into the camera menu. Good Luck and Enjoy your Nikons!
I own both the D5100 and the D7000. If I had to chose only one of them to keep, it would be the D7000. It eclipses the D5100 in funtions easily. My only reason for having the D5100 is the articulating LCD panel.
I have both the D5100 and D7000. Started with the D5100 but quickly found I was limited by the controls.
The D5100 took beautiful photos - see my gallery of the Wnter Jam concert. But when I wanted to get more creative, or push the camera, I found the controls somewhat lacking on D5100. The D7000 has flash commander mode, and the D5100 does not.
I use the D5100 as a back up and travel camera and the D7000 for assignments and serious work..
I prefer the light weight of the D5100 over the D7000, that' s one of the reasons I use it for travel and street photography.
I have the 5100 I was considering the D7000 before I got it and looked at both and got the D5100 as I like the pull out screen feature you can get a lot of different perspectives with it. I'm semi pro and can't tell you how much I use it shooting over the heads of crowds or to get a low angle perspective of a shot. I dont know why more full frames don't have this feature once you use it your hooked Sonys new A99 full frame camera will have it. The D5100 and D7000 have the same sensor the D7000 has more buttons and better weather sealing the D5100 is more menu driven. Hope this helps