New camera or new lens?

I currently have a nikon d3100 with the kit 18-55mm and a 28mm. I find myself wanting to take lots of macros and would really like an 85mm micro but don't know if its worth it on my d3100. Should I get the new lens or trade the body and cash for a new body?

Does the 3100 give you the results you're looking far, quality-wise? If so, keep it & spring for a new lens.

Typical beginner mistake… Definitely buy a new lens. Buying a nicer camera (such as the D5100) and using the same lens will give you the same image quality as your D3100. But the same camera + new lens = better quality. And the term macro refers to a 1:1 reproduction ratio (subject size: image size), not how close you are to the subject you're photographing.

Until you have owned your D3100 for four or five years, it is doubtful that you will have been able to use all of its features intuitivily. Better to start building your camera system with a number of specific AF-S lenses.

In 2015, the technology in those new cameras will make it a good time to buy another dSLR body, keeping your fine D3100 as a second camera so you can shoot things like sports when having two cameras, each with a different lens attached is almost mandatory

I would suggest getting a new lens