Don't get too excited just yet - this is a Dunnington server part based on Penryn, not Nehalem:
|Dunnington is its name and pairing up three Wolfdale cores is its game. Intel's first six-core processor, which is set to start shipping on September 15, is the Xeon X7460 and it is part of the server-prone Xeon 7400 series. The X7640 is pin compatible with today's Xeon processors and it features six cores clocked at (about) 2.53 GHz, have 3MB of L2 cache per two cores and 16MB of shared L3 cache.
The Dunnington processors are expected to be last Penryn-based server parts as Intel is gearing up to release a whole new line-up of Nehalem-based CPUs, the Nehalem-EP and Nehalem-EX.