“Can someone tell me if new energy efficiant windows qualify for the residential energy credit?”---->Residential Energy Property Credit (Section 1121): The new law increases the energy tax credit for homeowners who make energy efficient improvements,i.e., energy efficient exterior windows, to their existing homes. The new law increases the credit rate to 30 percent of the cost of all qualifying improvements and raises the maximum credit limit to $1,500 for improvements placed in service in 2009 and 2010.
Please visit the IRS website here;
Energy Provisions of the American Recovery and Reinvestment Act of 2009
Residential Energy credit 
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