http://xtreview.com/images/character...essors%201.jpg The i7-3930K and i7-3960X preempted the i7-3770K by at least 2 quarters. The i7-3820 preempted the i7-3770K by at least 1 quarter. Seeing as how CPU generations are approximately 1 year, Sandy Bridge-E is slightly older (especially noted by 32nm fabrication over 22nm).
Quad channel RAM, while useful for servers, is not necessary for gaming. Most of the advantages offered by the X79 chipset do not offset its large price premium.
Ivy bridges can also be overclocked to 4.5 GHz and 5.0 GHz if you're an enthusiast.
The 2011 socket started in Q4'11 as shown in
http://xtreview.com/images/character...essors%201.jpg so it is coming up on a year old.
The only reason to purchase a socket 2011 is for Ivy Bridge-E support which will no doubt also come with a new chipset rendering the x79 obsolete.