Apple announced an Intel Xeon Core 2 (Woodcrest) based Mac Pro desktop today at the WWDC06.

Every Mac Pro in the lineup features two of the newest Dual-Core Intel Xeon processors. 2GHz, 2.66GHz, or 3GHz are available. At 3GHz, the Mac Pro runs up to 2x faster than the Power Mac G5 Quad.

You can put up to 2TB of storage in you Mac Pro. The power machine offers 8 DIMM slots to fill with up to 16GB of RAM. It provides space for up to two SuperDrives. You also have four PCI Express slots, and more I/O ports.
The Mac Pro is the fastest and most configurable Apple computer of all times.
The standard configuratio of the Mac Pro with 2 2.66Ghz CPUs, 1GB RAM and 250GB HDD sells for $2,499.
More about the new Apple Pro on this Apple product page.