17th
This is a great and well thought-out post. As supporting evidence, at least anecdotally, I know of 3 different very high-profile social media experts who already have or are planning to segue into something else because they see their role as more of a job and less of a career per se. Even at marketing and PR firms where these individuals are in relatively high demand right now, the internal goal (correctly) is to move towards a place where social media becomes a core competency, part of everyone’s collective toolbelt — and therefore no longer just some dude or gal in a corner who what what the heck machinima is. (A lot of firms talk like this is the already the case in their organization but it’s just that — talk.) Hehe.
Any true social media expert spends the bulk of his or her time teaching — the endgame is that you teach yourself out of a job. I agree with Jason Kinzler in the comments that these roles will never truly vanish, but we are well past the peak in my mind and again, a number of high-profile people have clearly seen the writing on the wall. I’ve been thinking about this same issue a lot myself. The Webmaster is a great analogy.

