Doesn't work! the IRS site is too sensitive to how you enter your information. It could not find my tax return even after I entered the information multiple ways. caps, no caps. Apartment number, no apartment number, Periods, no periods. It simply does not work.
Answer:
Well, it's still kind of early. They say it will work for "most users" as early as Jan. 30. Also, perhaps you need to wait the full two weeks after you've filed your taxes. I would definitely call the help number on the online FAFSA form, and see if they can assist you.
*Update* The 2012-2013 FAFSA IRS data transfer seems to be going much smoother, without any delays or information lost. Unlike last year, there have been no reports of users having difficulties.