If u are going to use multi-threading require software, tat will be a more performance different between them.
But if u are only use for gaming , i5-3470 is better choice for it is more cheap and if u wan get i5-3570 , u better get i5-3570K.
Friend of mine got the 3470 and i got the 3570 for the same price as the 3470 on sale down from 219 to 179. Really the difference is minimal at best. You won't even know the difference. I tend to wait for email promos and jump on them. (why always pay full price?)
The trend lately seems like as long as you have a top tiered CPU (those are both in the top tier) combined with a really decent 2 GB graphics card ( ie: 7870 AMD, 7950, or nvidia 670, 680) you will get the best results. Games released now almost will use the entire 2 GB with ultra/high settings. Probably by next year 3 GB will be the sweet spot.
So to answer your question - My intel 3570 (non k) combined with AMD 6950 runs everything fine at 1080p. I was doubtful with Bioshock Infinite but it plays smooth!. I'm holding off for a sale on the 7970 which would be a big jump from what i have now. At this point it doesn't make sense.