It's well known that many bloggers opt to keep their identity hidden for fear of possible consequences from expressing their opinions, such as problems with their employers and political persecution in countries where dissent isn't tolerated.

Google officials have said that they plan to allow for the use of pseudonyms in Google+ at some point, but it's unclear when that will happen and to what extent it will be possible to withhold one's real identity.

At this point, it's not required for users of Google services to have a Google+ account. However, people who do opt to join Google+ must first set up a public Google Profile which, at minimum, must make their real name visible to anyone who views the page.