This new 3.46GHz clocked Core i7 Extreme 990X should last all the way to the end of Q3 2011 and in Q4 2011, Intel plans to launch a new high end CPU based on Sandy Bridge E CPU. The new CPU's can have up to eight cores, but our sources are clueless whether this is a six- or eight-core extreme processor.
Intel i7 970 also gets replaced by Sandy Bridge E unlocked CPU and Core i7 2600K and Core i7 960 will get its own replacement with Sandy Bridge E. This might indicate two versions of the Sandy Bridge E CPU, a quad- and six- or eight-core, but this is a pure speculation at this time.
All of them are coming in Q4 2011 and they will last at least through the first half of 2012.
