the socialization of everything

The 19th through 20th centuries were marked by the rise in individual privacy and increases in solitary behavior.

• Dating as couples became the norm among young people, in contrast with primarily socializing in groups.
• It became less common for neighbors to be considered automatic friends, and in some neighborhoods, even to know each other.
• Fewer people joined clubs and other social groups, as pointed out in Bowling Alone, by Robert D. Putnam (2000). In fact, in some communities some such groups went from being respected and membership being considered socially necessary, to being considered "hokey." How many teenaged Scouts do you know? For that matter, how many kids do you know who went beyond Cub Scouts or Brownies?
• Television went from a community experience shared with friends and neighbors, to a family experience, to individuals having their own sets in their bedrooms.
• Groups of friends used to get together to listen to records. Beginning with the Walkman in the early 1980s, music became something often listened to through earphones on a personal device.
• Games went from mostly being played by two or more people around a table to being played by one person in front of a computer. I remember when early video arcade games like Asteroids and Pac Man began to replace pinball machines in the student union. Looking back, I realize that it was more usual -- more "normal" -- to see a person playing those games alone than to see a lone pinball player without friends standing around watching while they waited for their turn. Solitaire had a reputation for being played by pathetically lonely people. Few admitted to playing it. There seems to be no such connotation or shame with computer solitaire.
• The "populars" became a bit less universally worshipfully respected and the "nerds" a bit less despised. Respect for diversity and awareness of conditions such as Asperger's syndrome made people realize that not everyone is socially inclined; parents, teachers, and other caregivers became less likely to see shyness as a severely harmful character flaw or a sin. (Yes, people still laughed at the Trekkie in his parents' basement, but for the first time, there was sometimes some affection in that laugh.)
  

Recently, the tide seems to be turning.

• Scientific research is placing more and more emphasis on the social aspects of the human experience. In The Ape that Spoke (1991), John McCrone presents a theory that human language began, not for practical hunting, gathering, tool-making, or survival reasons, but to keep track of social interactions and relationships and interact socially -- to gossip and schmooze.
  
• In Gen Buy (2009), Kit Yarrow points out that the current generation of teens and young adults are more likely to socialize in groups (and especially shop in groups -- this is a business advice book), and to consult their peers before doing things (especially before buying things).
• More and more computer games are made to be played against human opponents rather than the computer. The social component is even greater in online multiplayer games like Runescape and World of Warcraft.
• Console video games have always been come with two or more controllers so that people could play together, but the games provided equally for a single-player experience. The games which seem to be growing most in popularity are ones like Rock Band and Wii Sports, which are primarily designed to be for multiple players.
• Web authoring has become social with the rise of blogging and microblogging, which provides a place for reader comments, as do many national and local news sites. Many blog hosting sites make it possible to turn the commenting function off, but a blogger who does so will be seen as unfriendly.
• Websites created solely for social interaction, such as Facebook and MySpace, are among the top sites on the internet.
• There's an increasing tendency for any activity done in public to be done in pairs or larger groups. Now few people seem to even study alone. Until recently, many, if not most, of the people at public libraries (excepting, of course, children young enough to need a parent with them) came alone. They got their books and went home to read alone, or sat in the library reading or writing alone. There's a reason many libraries had solitary study carrels. Even when families or friends came together, the individuals in the group usually had their own agendas, their own books to look for. Recently the shift is toward groups coming in and doing everything together. Many of the requests we get at the reference desk are for someone else in the group -- "My sister needs help," "My friend's computer crashed," "My husband is looking for the westerns," "My cousin..." Chairs are moved from individual carrels and individual places at tables and clustered around computers. The chairs left at the tables are moved from their rows and grouped into configurations better suited to conversation and sharing books or a notebook computer.
  

Some reasons for the shift may be technological, e.g., social websites and cell phones make it convenient to keep in touch with many people. And some may be cultural; more working class people, who tend to be suspicious of private activity, now are using computers, and there are more people from non-western-European cultures who place a high value on doing things in family or friend groups. But there does seem to be a definite shift toward more social behavior, and with it a change in norms and values.