Hi Behzad,I did not advise you to try the EOS7 only because I have no knowledge of it, so I cant advise you on lenses.
Originally Posted by Behzad
The Nikon D7000 is getting very good reviews though, if weight is not an issue.The D60 is now quite old and probably the D3100 would be better as it's the latest entry level Nikon.
As I may have mentioned before dont forget you are buying iinto a lens system,I went from Canon to Nikon when I went digital because I liked the Nikor lens particularly.
You can compare sample images of different cameras on this site which you may find interesting
Just as a matter of interest my old Nikon D40X turned out some cracking shots,so you wont go wrong with any of these cameras.
See Ken Rockwells site,some good info there but some of it appears to be a bit tongue in cheek.