Just to add in my experience with the field, unlike the OP, I wasn't so successful with turning social media into a career. I have an MBA in Marketing and have been doing independent/freelance web design for several years. Managing social media accounts for some of my clients became a part of that. Well in January of this year, I took a contract position with a web company that basically promoted viral web content via social media. What I found is that it was more of a game to generate web traffic and boost SEO rather than really engaging people and having a conversation. I mean it had it's place, in that people who were looking for web content and/or links could use us as a resource (sort of like Mashable....but more technology based). Anyway, I really grew to dislike the process...and quit to go back to a more traditional career.
All in all, it wasn't a bad experience. It just wasn't for me.