Haswell-E for gaming? Are you kidding? Now, I certainly appreciate many core CPUs but we're still in a situation where the vast majority of games are optimized for 1-2 threads, 4 if you're lucky. The games that take advantage of anything beyond that are ridiculously few and far between.
There's also cost involved, i'm not sure if that matters to you, but if it does - A Devil's canyon will deliver 100% or more performance in most games compared to Haswell-E. In fact, DC should be faster in most games that aren't optimized for hexa core (which is 99%+ of them). A good hexa core will be 550$ for the CPU itself and 300$ for a good motherboard. A quad core mainstream part will be around 200$ for an unlocked CPU (around 4670k level) and 100-200$ for the motherboard.
Now, obviously, budget may mean little to you. But suggesting an 8 core for gaming is outright lunacy at this point and time. The extra money you spend doesn't translate into more performance; the performance is generally identical or greater with the mainstream CPU, period.
The question is whether in the next 6 months if games take advantage of 6-8 core CPUs. I think the answer will likely be no, because the vast majority of the gaming audience is on either dual core or quad core. But you can re-evaluate that closer to launch; yet the current situation heavily favors the mainstream platform over the HEDT platform for _PC GAMING_.