Should you wait for it to snow...?
I mean, you can wait, but the snow will melt and go...
Bad analogy, but what I mean by that is why wait for Haswell when a new architecture is likely to be released the year after?
I always upgrade to whatever is best for NOW, not later - because as with all things computer land, it will be obsolete the next day anyway.
You could upgrade now and still be in for a ride for the next 2 years, I mean the prices are only likely to get better, right?