As a community manager for a large internet company, I interact with our users (and moderators!) on a fairly consistent basis. In fact, I often spend large swaths of my day in the main moderator chatroom, handling moderator issues and contributing to the conversation that is going on.
Moderators are unpaid users who cultivate and police a site. (By contrast, I am an official employee of the company, and I receive a salary.) Also, from certain perspectives, I'm a moderator or user's first line of appeal, meaning that if an issue requires escalation, I'm one of a group of people they turn to first.
I've been fortunate enough to be able to meet some of these moderators and users in Real Life. I find I get along well with some of them, and enjoy spending time with them.
Is it unprofessional for me to pursue friendships and personal relationships with these users?