This just in from a Mortgage lady I refer to:

The $7500 tax credit for first time buyers is a great thing to help stimulate interest.  There have been a lot of questions and little clarification.  The Tax groups are finally getting some information.  Here is a recent clarification:  

 Unmarried couples get a break on claiming the new credit for home buyers.  They can allocate the credit any way they want.  Example:  If one of the two unmarried purchasers has more than $95,000 of AGI, the credit can be allocated in full to the other buyer.  Similarly, if one of the buyers has owned a principal residence in the past three years and thus is not eligible to claim the credit, the entire credit can be taken by the other.  The maximum credit is 10% of the purchase price, but not more than $7500.  For homes purchased in the first 6 months of 2009, buyers can claim the credit on their 2008 return or they can file an amended return.  When filing a joint tax return as a married couple, neither buyer can have owned a home in the last 3 years.

Missouri Housing Development Corporation has come up with a program in which buyers can "borrow" against the $7500, up front, for their downpayment, and pay MHDC back when they receive their funds.  Missouri is the first state to come up with a program to get the money up front to help with downpayment.