I think you are debating something without having all the facts - facts that will be released shortly once we get the D7000 in member hands for some testing. Your comparison is a bit of apples and oranges. We all agree that larger pixel size reduces noise in low light/high ISO situations if all factors are equal, but all factors are not equal.
According to Nikon, the D7000 specs for ISO performance and noise are comparable to the D700. ISO noise is not even relevant for most images as most images are with ISO 100-200. In addition, the software makes a difference and we can expect that Nikon has tweaked the camera processor to further improve high ISO noise performance.
The D7000 does have 16.9 megapixels - which is a nice step up from all but the D3x. In some cases more pixels are better. The practical side of this is for most photographers the 12 megapixel sensor is fully adequate for prints up to 20 x 30.