MacRumors.com

AppleInsider claims they have confirmation that Apple will be using Intel's Xeon 5100 series processors, also known as "Woodcrest" to power their next generation Intel-based Mac Pro Workstations.

Previous claims indicated that the Mac Pro would continue the Quad-core tradition set by the latest batch of PowerMac G5's. However, in order for an Intel-based "Quad" to be developed, a multi-processor machine would be required, which inherently leaves out the use of Core 2 Duo "Conroe" based microprocessors, as they do not support multi-processor configurations.

Of note, ThinkSecret has maintained that they believe the Mac Pro will utilize Core 2 Duo (Conroe).

Additionally, AppleInsider speculates that Conroe may be used in a future iMac revision, while Merom will be used in future MacBook Pros and Yonah will remain in the MacBook and Mac Mini.