First they talked about Brittany, about her face-blindness. They talked about what a commenter identified as auditory processing disabilities. I think there are reasonable arguments for those things. Someone talked about how they thought Rachel was narcissistic, which I thought was also quite reasonable.
Kurt got a couple of possible diagnoses. One was that he was depressed for parts of seasons one and two, and then again for parts of season four. They thought it was situational depression. Another bit of discussion was that he had traits from the autism spectrum. The panelists said "high-functioning," which terminology ("high-functioning"/"low-functioning"
Blaine got several diagnoses: anxiety, depression, cyclothymia and PTSD. Cyclothymia is apparently like a mild version of being bipolar. I could see how someone could perceive Blaine as going from hypomanic to depressed in cycles. I thought there was a good argument for Blaine having PTSD. Blaine usually puts up a good front, but I thought the theories about Blaine having anxiety and depression were reasonable.
The fictional Lima, Ohio seems to create anxiety and depression in a lot of characters. It may be worse for the queer characters, but few characters seem untouched.
I wish I'd known who was talking when, but I thought the podcast was a pretty good one.