Why is Facebook becoming increasingly unfriendly?

Based on the continuing rise in the popularity of Facebook, which adds another 100 million users about every six months, and the overall increase in the percentage of those users who have unfriended someone,  more than a half a billion people experienced the sting of rejection on the site in 2011, compared to approximately 158 million in 2009. Some of this increase may simply be a reflection of the larger universe now involved in managing their friendships. The odds of wanting to hold onto all of your friends, after all, are likely to decrease as the group gets larger and larger.

But another reason for this increase may be the shifting generational demographics of Facebook users. Today, more than half of Facebook users are over 35.  In 2009, that group represented only one-third of all users. As older generations catch up with the proportion of Millennials (born 1982-2003) participating in Facebook, the site's users are less likely to share the Millennial penchant for openness, sharing, and group-oriented behavior.

Fifty  and 60-year old Boomers (born 1946-1964), for instance, as well as even older members of the Silent Generation (born 1925-1945),  are more concerned with  preserving their privacy than younger generations are. Given Facebook's increased emphasis on sharing everything, older users are likely to exercise more control over their friends list and limit them to those people they feel particularly close to or trust more.

While need for privacy may also be of concern to Generation X, sandwiched between Millennials and Boomers, their generation brings an entirely different sensibility to social media.  They see it as yet another technological tool to make life easier to manage. Their concern for efficiency and speed may well lead them to drop friends whose utilitarian value, at least on Facebook, is no longer apparent, especially as the universe of potential friends expands.

The commercial implications of this increase in unfriending activity present a problem for Facebook. Its pending IPO depends on increasing the amount of revenue per subscriber that the site generates.  This now lags significantly behind that of other social media sites such as Google.  Advertisers hope that with new features, such as Timeline, and a renewed focus on helping major brands target their advertising by Facebook, they will begin to see more bang for their online bucks.

However, it may become difficult to fulfill this hope as the universe of Facebook users begins to approach the earth's connected population. Even though studies have shown Facebook users to have more close relationships than other Internet users, the distinction between Facebook users and everyone else will continue to erode as the two populations merge into one. At that point, everyone will be engaged in the process of limiting their friends to those they really care about and billions of people will experience the sharp but momentary pain of being unfriended.