do you plan on doing any overclocking? if so then go with ivy bridge as haswell produces more heat and has less headroom for overclocking. if not then get a non K haswell as it will have higher performance than ivy (not by much but then again, if you aren't overclocking then what you get is what you get).
Dont opt for a haswell over ivy
1. Only 5-10% marginal increase in haswell from ivy
2.haswell produces more heat than 6 core sandy bridge e processors so ivy cpu would b better overclocker
3.there is no news that the 1150 socket would support further generation processors