How the New First-Time Buyer Tax Credit Works, an article from Realtor Magazine Online, reports that under the new housing bill, home buyers who have not owned a home in the last three years will be eligible for a tax credit equal to 10% of the property up to a maximum of $7,500.  The program is a loan, which home buyers must repay over 15 years at 0% interest beginning in the second year after they purchase the home.  For example, a home buyer who qualified for the whole credit would pay $500 for 15 years or about $41.67 per month.  The credit applies only to homes purchased on or after April 9, 2008, and before July 1, 2009.
http://www.realtor.org/rmodaily.nsf/pages/News2008080402