Today, at Intel's Developer Forum, Intel spoke about the new Conroe core. They mentioned a few key features they are bringing to the table, not surprisingly many of them focused on power and security. They've also made many core revisions, such as a length reduction in the processor pipelines. Overall, you're looking at a TDP of 65W, much better than the Prescotts that approach and surpass 130W at times, for 40% less power consumed, shared L2 cached (better than unified) per core, along with a significant performance increase over a comparable Pentium D.
After a few shoddy starts, the P4-D may start to turn around nicely, and at looks like that is what is happening with Conroe (at least on paper). Great stuff, and it will be very interesting to see if it is really pulled off.