ASE Labs posted the latest roadmap from Intel
I am sure everyone is familiar with Intel's processor numbering system. With the current system today, there are 3xx,5xx, and 7xx lines of CPUs. The 6xx line just came out and is the Pentium 4 with EM64T (x86-64). The 3xx series contains the Celeron M and the Celeron D lines. The 5xx series contains the Penitum 4 with Hyper Threading. The 7xx line is the Pentium M line for notebooks. The new 6xx line has EM64T as mentioned and also contains the new revision of the Prescott core containing 2MB of cache and SpeedStep. Extreme Edition CPUs do not use the model number rule and are marketted by clock speed. Shown at the conference is the not yet released 8xx line of CPUs. These will be marketted as Pentium D (notice that it does not contain '4' in the name). The 8xx line will be Intel's dual core CPU (codenamed Smithfield) line and will run at 800MHz FSB and higher. These CPUs will not contain Hyper-Threading. They will contain 2x1MB of cache, meaning that each core will have its own 1MB of L2 cache. The 820 will run at 2.8GHz, the 830 will run at 3GHz, and the 840 will run at 3.2GHz. All new desktop CPUs will be using the LGA775 package.Intel - May 2005
You'll also notice a refresh on the 5xx and the 3xx line of CPUs. If you notice a model number ending in 1 or 6, it contains EM64T.