One would think that this should have happened sooner….but, well, there is a human tradition here…Wikipedia currently lists 342 social media apps, emphasizing up front that their list is not exhaustive. I can think of at least two more local social media startups, one of which has just announced significant new investments. Extraordinary Popular Delusions and The Madness of Crowds, the now legendary book by Charles Mackay, first published in 1841, remains a classic text revered for its insights into social psychology and economic bubbles.