I currently have a Nikon D5000.

I have the opportunity to purchase a Nikon D90 (body only) as a second camera.

From what I understand, the D90 and D5000 are fairly similar.

If I do purchase a second camera, should I purchase something similar to what I have or look for something different?

Being somewhat of a hobbyist photographer at the moment, do I really need a second camera?

Perhaps an odd question, but not sure what to do.

Thanks!