Unabashed racism, homophobia and jingoism. Most people I've gotten to know there start out super friendly and then repugnant beliefs start to emerge as we've become more familiar. I've heard similar stories from other transplants.
eta: I'm not saying this is a universal problem with the south. I'm just saying that I've noticed it there far more often than in other places I've lived and traveled.
in the south, i have had way more people scream homophobic epithets at me on the street. not sure why because i'm heterosexual, and one time a car full of old women screamed a lesbian-focused epithet at myself and my wife while we were walking hand in hand.
i grew up in the south and i have no idea what southern hospitality means. where i lived, the running joke about southern hospitality was that <ethnic group> would hear the sound of you reloading before you opened fire.
if you're nerved out when surrounded by a bunch of well-armed, perpetually drunk, ill mannered, poorly educated and xenophobic people, i would not recommend moving to the south.
I think that there is an element of California (inland) that you would recognize as similar to elements of the South (mega churches, militant anti-abortion sentiment, amazing amounts of poverty).
You might just be shocked at the level of homophobia, however. When I lived in Atlanta I worked with a couple who once confided that they had enough scary experiences that they quickly told everyone they were sisters when traveling outside of Atlanta.
eta: I'm not saying this is a universal problem with the south. I'm just saying that I've noticed it there far more often than in other places I've lived and traveled.