Intel has yet to determine what brand they will market their first desktop chips under, although we'd expect them to continue to use the Pentium 4 brand but with some sort of appendage like Extreme Edition or Lots of Cores Version. Intel has, however, already determined what the specifications and the model numbers of their dual core chips will be.
Currently set for release in Q3 2005, Intel has three dual core chips on their desktop roadmap: the x20, x30 and x40. The only difference between these three chips is clock speed, with the x20 running at 2.8GHz, the x30 running at 3GHz and the x40 running at 3.2GHz. All of the chips are LGA-775 compatible and run off of an 800MHz FSB. Hyper-Threading is not enabled with Intel's dual core chips..
The whole article about Intel's DC processors can be found at AnandTech