If you mean did it help more houses to sell at perhaps a higher price than they would have otherwise until the credit ended I am sure it helped.
If you mean did it help the housing market to really stabilize so prices will not drop for the next few years the answer is no, it did not help.
Did the credit help more buyers to buy this summer? Absolutely not!!! It is over. It cost you the buyers who bought then and normally would be buying now.
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WILL THEY BRING BACK ANOTHER TAX CREDIT FOR BUYER?