Personally, I strongly weight city/friends in job decisions. The job is 8hrs of my life. The environs and people I enjoy it with influence all the other time (less sleeping). Having friends in the area is a multiplier for all the things I could enjoy myself (theatre, costume parties, etc) and is a good filter for hearing about other things I'll enjoy.

You can, of course, make new friends wherever you go, but I really like keeping the norm of maintaining particularly close friendships instead of having a bunch of one-to-two year connections. You can try to keep up close connections long distance but, outside view, you won't.