I'll give you two answers: the first is about people from Edinburgh in general, and the second is about its students.
Edinburgh is the only middle-class city in Scotland. I'm from here (I don't go to uni' here, but I live here). As a result there is a clear distinction between those from Edinburgh and those from other parts of Scotland.
Generally, if you're not from Edinburgh, and you're Scottish, then we're not really interested in you. It's similar to Londoners not caring about anyone else unless they're from London.
It's more of a social thing though. What do I mean? I mean social manners, interests and the etiquette mentality of the traditional (emphasis on traditional) middle-class.
We find that the rest of Scotland (I am not arguing this conclusively, so I'm not arguing inductively) are crude, abrupt and lacking manners.
Are we stuck up? Not necessarily. We just look down on people if they are rough, crude and generally the opposite of etiquette. 'That makes you sound like a stuck up fool', one might say. Well, we are only like this because we are not rough, crude and are etiquette. Be objective.
About the students at Edinburgh, it's mixed. You'll find what you're looking for social group wise. Is there class segregation? In some places, yes. It will entirely depend on the people - we are all individuals remember. A lot will be moulded by interests - social classes have similar interests e.g. rugby is a more middle-class game and football a more working-class game. Thus class segregation arises due to factors such as this. However it is more of an interest thing than 'you're a different class so this is awkward' predicament. Class is a mere association, sometimes.
Whoever and whatever you are (generally), you'll find your place.
I hope you enjoy my wonderful city. I know I'm going to miss it terribly when I go to uni'.