First thing firs the reasons for comparisons:
1. Intel did not have a daily use premium processor thus far either it was the Mammoth Xeon processors or the Ivy Bridge i7s or i5s.
2. The Xeon could only be afforded by large firms and institutions due to its very high purchase as well as maintenance cost, leaving small businesses and server owners stranded and made to use the 'cheaper' processors consumer processors.
So keeping all this in mind lets take a brief look at the key features of these two titans:
Clearly these two are as different as they get but then they cater to two different markets after all. Taking a deeper plunge into the details i came across this:
Intel Core i7-3960X advantages
Intel Xeon E5-2687W advantages
As seen clearly the i7 3970K is dominating over the Xeon E5 2687W but this is because of two prime reasons the i7 was intended to function on a single processor motherboard unlike the Xeon that works in a pair as it is a server or processor. Intel launched the 3970K just to give the consumers a taste of what its like to use a high end processors and even help owners of small servers like that of regional universities to graphic designer to get better performance without spending a bomb!
Also the Xeon can support more RAM than the 3960X, with 750GB vs 64GB making it still the first choice for heavy servers.
My Verdict:Frankly speaking these two just can't be compared on any basis sending Intel's expectations to keep them in the same bracket to the rock-bottom! The only thing that can come out of this is the fact that definitely Intel has managed to bridge the gap between the big players and the still emerging ones giving the latter a still cheaper/performance hardware to boost up their work giving them some relief and the space to improve their working capacity, something what AMD couldn't do so far as the latest FX 9590 is still not for consumer sale whereas the Intel i7 3970K is a consumer hardware! So if you are planning to setup a small business or a server for a local university or office etc then a central CPU with the 3970K in it is the right choice for you whereas if you are the blesses ones, then still the Goliath of a processor the Intel Xeon E5-2687W is what you are looking for.
So if you have any other query regarding the same or any suggestion or point that you would like to add please let me know.