Only difference between the 3570 and 3470 is .2GHz for an extra $20. I personally do not think this is worth the extra $20, but is it?
Worth is something only YOU can determine.
The price/performance equation says no. you are getting a 6% improvement for a 10% cost.
But... comparing a 3570 to a 3570K and the potential for a 30% overclock at a 10% price delta, that is a much better buy.