Hey guys! I'm a Californian-Oklahoman. I've lived in both sates as well as abroad and I can tell you a lot about Norman because I did my undergrad at OU!
Okay, here's the skinny: Norman is a college town. It's about 110,000 Population and is intensely segregated by occupation/income. the Middle of the city is totally run by the university. It's about a 3 by 5 mile square of densely populated homes, duplexes and apartments with the University in the middle. Within this square you will see students and locals riding bicycles, many Obama signs on cars and yards and you will see professors and their families as well as a lot of Normanites who either went to OU and stuck around or are "taking some time off". It's a liberal vibe and there are quite an array of bars and coffee shops. You can live here without a car, and there are collective communes here and there. Looots of hipsters as of recent years, and like any college town in 2013, a sizable LGBT population and vegan/new age. As far as Oklahoma goes, and really much of this part of the country, Norman is liberal. You certainly won't be chastized for having liberal views and you will find many others who feel the same. It's a university!
That said, there is a healthy conservative element. There is a sizable greek population at OU, with our sororities and fraternities being regionally notable. They tend to be less liberal and flaunt typical excessive consumerism mostly feeding in from Dallas and Houston (OU is roughly 60% Texan). But they aren't so bad, and there are liberals amongst them as well.
Anyway, anything else you all would like to know? I'd be happy to answer any questions!