Steve Jobs has made a statement to the Cupertino Council on Wednesday proposing a plan for a brand new Apple campus. The land is currently taken up with buildings but they will be razed and rebuilt to suit Apple's needs.
In his Statement Steve Jobs said that the companies business had tripled over the past 5 or 6 years and it will take a further 4 years to design and build the new campus. The new buildings are expected to hold 3000 to 3,500 employees.
[Update] Just to confirm, a source close to World of Apple has confirmed the destination of the new campus as Pruneridge Avenue, just off the I-280, just a couple of miles from Infinite Loop.