Intel announced the Core 2 Extreme X7900 yesterday at Games Convention 2007.
The 2.8GHz Merom processor offers a 4MB L2 cache with support for 800MHz Front Side Bus.
Readers will recognize this chip as the chip that was announced in the iMac on August 7th as a high end configuration. It appears that Apple is able to get preferential shipments on upcoming Intel processors. Intel had previously provided Apple with a 3.0GHz Xeon (Clovertown) processor with an early limited production.