There is a good article in the August 20th, 2004 issue of Psychiatric Times reporting on a survey done in Houston which shows that stigma towards people suffering from psychiatric disorders is on the decline.
According to a survey of 650 Houston-area residents conducted last spring by the Center for Public Policy at the University of Houston, 63 percent believe mental illness is primarily due to a brain disorder, while just 5 percent believe it is due to a character flaw.
The remainder of respondents attributed mental illness to "something else," including a genetic disorder (10 percent), the person's home environment (9 percent), a chemical imbalance (5 percent), or stress (5 percent), among other variables.
In addition, 86 percent of people surveyed said they believed that health insurance companies should be required to cover mental health treatment in the same way they do other illnesses.
Here is a good chart which shows the difference in attitudes between respondents who personally know someone suffering from a mental illness as compared to people with no personal knowledge. People with personal knowledge are much more likely to be supportive of less stigma.