It doesn't look good for the 750K. In the UK, pricing the same CPU and motherboard combinations on www.dabs.com yields a sizeable price advantage for the G3258:
AMD Athlon II X4 750K Black Edition 3.4GHz FM2 4MB 100W £54.09
MSI A78M-E35 AMD FM2+ A78 DDR3 mATX £39.99
Total £94.08
Intel Pentium Dual Core G3258 3.20GHz 3MB S1150 Pentium K Anniversary £47.98
MSI H81M-P33 S1150 Intel H81 DDR3 mATX £29.41
Total £77.39
In fact, these prices are significantly lower than the Amazon ones in this article...
AMD only has productivity as an advantage (and, I guess, the fact it's not lacking any features found in higher models), and the 760K won't change the performance for price result. They really needed a 770K Steamroller-class CPU; I would find it hard to believe that yields are so good that no throwaways exist. With the 750K and 760K being failed parts, AMD would get no money for them otherwise, so I think they can drop prices to beat Intel here.
One saving grace is the generally more consistent frame latency.