My cost-benefit analysis professor at George Washington University, Stephanie Riegg Cellini, has a working paper out on the returns to a for-profit college education. They are positive and not significnatly different from public community colleges (although they also say there is some evidence the return is higher - I'll have to read closer what the distinction is). Regardless, it's a positive finding for for-profit schools.
Stephanie is a really sharp economist, and I strongly suggest reading anything of hers that you see. She does a lot with the economics of education - the labor returns side of it, but also school financing issues.
We also have more in common than the class at GW. She was a research assistant at the Urban Institute, and worke with many of the people in LHP that I worked with (and still work with), before she went to Berkeley. My mentor at Urban, Bob Lerman, told me when I was applying that I was one of the most prepared applicants he had seen come out of UI. "You probably have more under your belt than Stephanie", he said. I considered that very high praise - although the admissions gods apparently felt differently! Stephanie is still quite young too. She was just starting at GW when I had her, and that was only three or four years ago at this point. I imagine she's going to have a very successful career.