Southwest carries more passengers than any other U.S. airline, but profits are sagging and there are seats to fill so it's finally going to sell tickets through the same booking engine other airlines use. But you're still not getting an assigned seat, Jill Barshay reports.

About a quarter of Americans currently infected with HIV don't know they're living with the virus, but the public health community is divided over the best way to find and treat that population. Janet Babin explains.