Usually, when someone applies for a refinance mortgage loan, an appraisal has to be done. However, this can lengthen the process and Fannie Mae and Freddie Mac have been ordered to streamline their loan modification programs. Waiving appraisals on refis may help with these efforts. National Mortgage News reports that refis are not the only types of mortgages getting another look:

Fannie Mae and Freddie Mac – with the blessing of their
regulator/conservator – are considering ways to expedite real estate
"short sales" and possibly waive appraisals to facilitate refinancings
of underwater mortgages.

Getting short sales through more quickly would also help the loan modification process. Fannie and Freddie are also in the midst of a mortgage moratorium, and Fannie plans to act as a landlord to many renters whose landlords have entered foreclosure.