Google's VP Bradley Horowitz mentioned that there are a few tweaks and new default settings for teens. By default, only the people from teens' circles can trigger notifications and comment on their public posts. If someone outside a teen's circles joins a hangout, Google+ temporarily removes the teen from the hangout and gives him a chance to rejoin.
Teens and young adults are the most active Internet users on the planet. And surprise, surprise: they're also human beings who enjoy spending time with friends and family. Put these two things together and it's clear that teens will increasingly connect online. Unfortunately, online sharing is still second-rate for this age group.
In life, for instance, teens can share the right things with just the right people (like classmates, parents or close ties). Over time, the nuance and richness of selective sharing even promotes authenticity and accountability. Sadly, today's most popular online tools are rigid and brittle by comparison, so teens end up over-sharing with all of their so-called "friends."
With Google+, we want to help teens build meaningful connections online. We also want to provide features that foster safety alongside self-expression. Today we're doing both, for everyone who's old enough for a Google Account.
It's interesting that the updated form for creating a Google Account doesn't automatically create a profile and doesn't add the user to Google+ if he's not at least 18 years old.
{ Thanks, Oskar. }