The document summarizes changes to the homebuyer tax credit that were enacted in November 2009. It provides a table comparing the rules for the credit from January to November 2009 and from December 2009 to April 2010. Key changes include expanding the credit to current homeowners of $6,500, setting an income limit of $125,000 for singles and $225,000 for married filing jointly, and requiring documentation be attached to tax returns to prevent fraud. The modifications go into effect when President Obama signs the bill.