Is it worth investing on a new lens?

Its been bothering me for months already whether I should buy a new SLR body or keep on using my old nikon D60 and maybe buy some new lenses. Any advice?

Added (1). Jeroen:

The D60 is not doing well in low light and the frames per sec is kinda slow for shooting sports. The D60 has only 3 focus points and I think that's not enough for shooting sports and moving objects like cars, etc.already have the 55-200mm lens which I already find enough for sports and sometimes I use it for portrait. So should I stick with what I have and maybe find a good lens online or maybe buy a new body? I'm also thinking about the D7000 to be used as a main body and the D60 as a back up body.

If you needed an other lens like the superwide angle 10-24 mm or a lens like the 70-300 mm for shooting sports, I would think that every time you picked up your camera to shoot such subjects, you would be thinking you need a second or third lens.

My feeling is you don't miss not having another lens. If that is true, look at the D7000.It should last you at least five years or so

No doubt, the lens is more important one good lens is better than several bad lenses