Both are excellent cameras.
The D90 was introduced in 2008.
The D7000 was introduced in 2010
The D7000 is a step up from the D90.
Here is a direct comparison of the two cameras:
http://snapsort.com/compare/Nikon_D7000-vs-Nikon_D90
.................
Great Picture:
Both cameras can take that Great Picture.
Just pointing the camera and pressing the shutter button will not produce a Great Picture.
It is up to you to recognize a Great Picture before you even turn-on the camera.
Sometimes the subject alone is a Great Picture.
Here is an example that I found on the Internet.
It does not matter what camera was used - the Dog's expression is the Great Picture, and
the photographer knew it.
http://img.photobucket.com/albums/v159/randol9p9/DogTub.jpg
The fun of photography is the search for a Great Picture.
Enjoy the hunt.
..
which camera i buy
is it nikon d90 or nikon d7000.
i want to take great picture...

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