to be fair... In my job, It does me very well to have 10+ VMs running on my desktop machine 24/7. Sandy Bridge-E (3930K, hex-core) was a god send for this. The 64 GB of RAM plays no small part as well, of course. I believe I left an E-8600 Core 2 Duo and 4 GB of RAM for this particular upgrade. Needless to say, for this workload, it was a fantastic upgrade. Obviously, there's been no value in leaving SB-E for IVB-E or now Haswell-E as the performance jump just is so minimal. Though, some of the cool things they've put on the silicon in these last 2 gens are enticing, but just not enough to leave for.
I'd say the coolest thing about Haswell-E is the X99 chipset. That chipset is drool worthy at 10 6Gb/s SATA ports, butt loads of PCIE lanes, and DDR4 support.