Best I can tell, the Senate amended a jobs bill a few hours ago to include a provision that extends the closing deadline for qualifying for the home buyer tax credit. This does not affect the deadline for being under contract, which remains at April 30 of this year. However, it helps an estimated 180,000 contracts that didn't look like they were going to close in time to qualify (I have 2 of them that are looking pretty dicey right now). The new proposed closing deadline is September 30 vs. the original June 30 deadline.
The link above seems to have the most accurate report of what is going on. A number of media reports would have you believe that this measure has passed into law but, if I understand this correctly, all that has really happened is that the senate approved this amendment and now they have to pass the jobs bill (which is expected) and reconcile it with a similar bill in the house. Of course, a lot can happen along the way.
No surprise, the real estate industry was lobbying hard on this one.