Yeah, you
could see a Mac Pro with whopping 8 CPU cores at the British Apple Store this morning. After they realized the mistake (or did it happen intentionally?) they took the wrong offering down.
The story behind that is quite simple. When the current Apple Mac Pro was introduced in August last year it was quite a performer around the Macs. Featuring two Dual Core Xeons (Xeon 5100 aka Woodcrest, up to 3GHz, 4 MByte shared L2-Cache), support for up to four PCI-E graphics cards (no SLI or Crossfire though) and a solid storage/network base it was very competitive compared to the PC workstations as well. But soon afterwards (in mid November) Intel revealed the Quad-Core-Xeons ('Clovertown').
Now it's finally time for Apple to unveil something new - obviously a Dual Quad-Core workstation, this time hopefully with full SLI or Crossfire support.
To add another theory, Apple will reveal a Quad-Core desktop Mac at the same time. At the moment the iMacs are based on Core 2 Duos (Merom) and that's it. I think there is plenty of room for a Kentsfield Mac...
Source: Mac Rumors