Looks like a Xeon, but It Is a Core Core 2 Quad Cores

The most powerful Xeon currently available, is the Penryn Xeon, featuring 12MB L2 cache, clocked at 3.2GHz, on a 1600MHz FSB. So far, Intel was really pushing Pro-oriented CPU vs. desktop CPUs, with Xeon getting the last technology development earlier than mass market CPUs. However, Intel just announced a future Core 2 Quad Core model (Extreme) which will have exactly the same specifications as the current high-end Xeon (US$ 1399).
However, only Xeon-dedicated motherboards can accept 2 CPUs, and we are still waiting for Apple to update the current Mac Pro line with the new high-end Penryn Xeon and faster motherboard.