DailyTech spotted Apple's UK site accidentally listed a dual quad-core Mac Pro computer on their site:
The listing, which Apple promptly found and removed, revealed the quad-core Mac Pro in search results when users searched for “Mac.” The quick description listed the Mac Pro as “Now quad-core or 8-core processing power. Configure yours today.”
Apple launched the Mac Pro, completing the PowerPC to Intel transition, last August. The Mac Pro featured dual Intel Xeon E5100-series processors paired with FB-DIMM memory. Shortly after the Mac Pro launch, users were able to swap in quad-core Clovertown processors without any hassle. Mac Pros ran flawlessly with dual quad-core Xeons without any BIOS updates or trickery.