The Intel Xeon 7400 Dunnington release and information go back to early this year. See the previous article from Engadget. The newest server chipset from Intel offers 6 Cores and is the last of the Penryn chipsets from Intel.
The 6 cores use technology from the upcoming Nahalem chipset that featuresl 6 cores of the processor on 1 piece of silicon. Traditionally anything over 2 cores were separated on their own pieces of silicon. The Xeon has much better performance than previous chips due to its 16Mb of L3 Cache.
Not the most exciting news unless you are into servers, but this is sure to trickle down to consumer hardware.
The expected date for the Launch is September 16th.
If you would like more info, see the video below