As with all rumors, please take the following news item with a grain of salt until we receive official confirmation or denial from Intel.
Intel has had quad-core CPUs on their road map for some time now, but the details have been very hard to come by until recently. Rumor has it that the high end part, the QX9300 will cost over $1000 and will feature a faster FSB to go with it's increased TDP:
“The Core 2 Extreme QX9300 will be manufactured at 45nm and have a core frequency of 2.53GHz. The CPU will come in a socket P package and support FSB speeds up to 1066MHz. The chip will include 12MB L2 cache and have a maximum TDP of 45W.”
The CPU should be available in the third quarter, just in time for the holidays.