I don't like Facebook at prices north of $20. But Bogle is wrong. It's not a fad. He's too old to remember how it fueled the Egyptian revolution, and many other countries effected by the Arab Spring.
Until the recent google panda and the very recent penguin updates. A major focus of seo strategy was using social networks to tweet or micro blog a few posts and then point those accounts to other more established accounts. Those more established accounts would then have some quality content with links back to you accounts. Now the above strategy might even been seen as legit for google juice. However there are automated programs which establish accounts and take content and spin it and do the same things. These programs create accounts by the dozens for each user of the software. They create phony blog networks and facebook accounts by the dozens or thousands... in an automated fashion. There is even a whole segment of the biz devoted to solving captures. such as companies like deathbycapture . There are thousands of these programs sold to seo guys and website owners. Google was being gamed by crappy content and fake social networking until recently. I would bet that close to half of facebooks accounts were set up for seo purposes. As a website owner I can tell you most of the websites which rank were gamed with social networking. For instance in the real estate industry frequently a few paragraphs and then a bunch of houses for sale. Just about Every website has the houses for sale (that is what most people are looking for when they got to a real estate website. But for those who try and put up real content... it can be very frustrating. You see crappy websites gamed with social networking and it pisses you off. Happily panda but more recently penguin seemed to return some quality websites up the ranks. but google has a long way to go. This who idea of links meaning something has been devalued by seo gaming. Google is working on idea such as author identification and google plus. But google plus seems to be stalling. keeping search relevent using algos is going to get tougher and tougher. -- here is a little background... but it is far more detailed and interesting. http://dailyseotip.com/say-bye-to-automated-seo-tools/1889/