Interesting essentially how little benefit they get.
The X99 mobo and platform is nice, I like a lot of what they're doing there, and all of the system components matter a lot to user experience. But unless you have a very specific requirement any user would be just as well served with a quad core or a octa core, if not better served with the devil's canyon quad core given the single threaded performance. That's probably a bad place for intel to be positioning these, as the target audience for these processors is looking for blazing fast and lots of cores. And it only delivers one of the two.
I think if I was buying a system this week or next (which... I am) I'd be a bit disappointed that I can't put a devil's canyon quad core on an X99 mobo, and then upgrade the CPU later if they manage to refresh the E series into something more attractive.