From yesterday's LA Times:
What's the best way to get an invite to try out Google+? Check its website regularly.

Google Inc. has begun letting more users check out its newest project -- but it's been sporadic. Google is letting current Google+ users send out invites at unspecified times as well as letting people simply sign on to the service if they check the website at the right moment.
Seems that many folks in the tech world are quite intrigued with the new offering from Google. Alexis Madrigal writes:

Yesterday on Google+ when a small group of friends were discussing the merits of the system, tech journalist Chris Mims pointed out this is a key advantage of Google's new social service. "Also it's a chance for a restart," he wrote. "I'm ignoring everyone whose name I don't recognize, simple as that. Some types of networks have a value in direct proportion to their selectivity."

I have an intuition that the network effect can sometimes reverse itself when people decide by change of life circumstance or growth or chance that their bonds enable a kind of bondage. The cry, "But my whole life is there!" can cut both ways. Americans love hitting the open road and getting a fresh start, and I wouldn't be surprised if we extended our love for residential mobility to the online domain.
I'm guessing many feel the same way, eager to trim and edit their "friends" list. (check out the article for a rather waggish illustration Madrigal created to capture the relative efficiency of "the social network effect). Included, below, are a couple of links that will bring you up to speed on the various features of Google+.

Google+ invites available sporadically
Salvador Rodriguez | 7 July 2011
latimesblogs.latimes.com/technology/2011...s-sporadically-.html

Google+: In Praise of Starting Over
Alexis Madrigal | 7 July 2011
www.theatlantic.com/technology/archive/2...tarting-over/241526/

The Google Plus 50
Chris Brogan | 3 July 2011
www.chrisbrogan.com/googleplus50/

Google+ is a marketing sensation
By Joe Wilcox | Published July 3, 2011
www.betanews.com/joewilcox/article/Googl...sensation/1309708375

There are even people suggesting that Google+ will replace Facebook.

Not being on FB, I can't compare the two, but G+ certainly also has the tendency to connect you to people you don't want to be contacted by (or don't even know), to the extent that articles are already appearing explaining how to adjust your settings to keep things more private.

I think as with any social network, the key for users will be in digging deep into the privacy settings to prevent inadvertent revelations to the world when you really meant to just communicate with a close friend or family member. Don't assume default settings protect privacy; on the contrary, they do everything they can to eliminate it.