A high-end Sandy Bridge, denoted with a letter E, will launch late this year in a 6-core, 12-thread configuration. It will also support quad-channel DDR3 and PCIe 2x16 graphics. Sandy Bridge-E will rule the "extreme" performance realm for at least until mid-2012.
Those looking beyond Sandy Bridge will get to see Intel's new process refresh of the technology in Ivy Bridge which will appear in the first half of 2012. Perhaps it will have a coming out party at CES in January 2012.