Since they share the same sensor, yes. The DxO tests do show the D3 with "slight" advantage. However, I would bet that a) you wouldn't notice the difference without looking for it, and, b) it probably falls within the normal sample variation. IMHO.
>Can someone explain why there is a difference between D700 >and the D3 ?
In the DXOMark testing methodology, they are evaluating RAW files using specific measurement techniques that provide objective and repeatable limits to their precision
The differences between the D3 and D700 by this method are so miniscule as to fall into the production performance differences between two samples of cameras. While the cameras probably both pass Nikon QC as an acceptable measurement accounting for component and system variance in production, the DXOMark tests on the RAW files will show up the tiny differences.