well, it's also going to save some power and allows larger amounts of memory. I'm just wondering why they would put it on the market in a month when nobody outside R&D labs has the hardware to use it yet.
Altera at the very least has FPGAs you can buy right now that offers DDR4 interfaces [1]. Also, I imagine a lot of this is directed towards OEMs who can get the early silicon samples of Haswell-E chips so they can start testing with them.
http://www.digikey.com/product-detail/en/10AX066H4F34I4SGES/...