What does color metering mean in cameras?

Http://imaging.nikon.com/products/imaging/lineup/digitalcamera/slr/d7000/compatibility02.htm
In the lens compatibility it says that the lense I want to buy is not compatible with metering color.yeah. Not sure what that means.help me? (=
Also, what does 3D metering mean?

Compatible lenses with D7000-
* DX AF NIKKOR: All functions supported
* Type G or D AF NIKKOR: All functions supported (PC Micro-NIKKOR does not support some functions); IX-NIKKOR lenses not supported
* Other AF NIKKOR: All functions supported except 3D color matrix metering II; lenses for F3AF not supported
* AI-P NIKKOR: All functions supported except 3D color matrix metering II
* Non-CPU: Can be used in modes A and M; color matrix metering and aperture value display supported if user provides lens data (AI lenses only)

3D Color matrix metering is a type of evaluative metering used by Nikon. As the name says it evaluates the whole scene and in layman terms you can consider it to compare it to a database of images to produce the exact results needed.

It relies on the following factors -
1. The overall brightness of the scene.
2. The differences in light measured across the pixel sensor data (i.e. The "patterns").
3. The focus area that has been selected (which the
camera assumes says something about where the
"subject" is located).
4. Distance information from the lens.
5. The color (or colors) of the areas measured.

It does away with compensation needed while photographing subjects with dark or light backgrounds, landscapes with sky or closeup photos with a blurred sky and a lot of other scenes you can think of.

3D matrix is at present the most advanced metering mode provided by Nikon.

It also is however not flawless. In case of dark filters (polarizers, and etc.) exposure compensation is needed. Some specific scenes also require exposure compensation.