Presler will be launched in the first quarter of 2006 and will be a dual-core 65nm part. It will feature two times 2MB L2 cache and Conroe will feature two times 4MB L2 cache. If you are wondering why they will feature two times L2 cache, well each processor core will get seperated L2 cache. That's why.
The Conroe will be an interesting chip as this processor will have a new architecture based on the Pentium M design. This means that Conroe won't use lots of power like the current Pentium 4 processors. This chip will likely mean the end of the Pentium 4.
Later this year Intel will launch the Pentium 4 673. This will be a 3.8GHz Cedar Mill chip with 800MHz FSB, 2M L2 cache, Virtualization Technology (VT), Hyper-Threading, EM64T, Enhanced Intel Speedstep Technology (EIST) and XD bit.
Another interesting evolution is the launch of desktop dual-core Yonah processors with the Calistoga chipset in the first quarter of 2006. It will be aimed at small form factor, all-in-one and entertainment PCs.