The Google+ invitation button has been available for more than a day now, suggesting Google is loosening up and is more confident about expanding its social network's population.

Of course, the company can still throttle the rate at which it delivers those invitations or the rate it signs up the new members when they open their invitations, but the relative ease I've had inviting folks to the service since Friday indicates to me that Google is loosening up, wrote Stephen Shankland of CNET.com.

Google+ invitations initially were only extended to a selective group of Googlers, tech critics, and some other people in the media industry, but the demand to join the plus project circle has been skyrocketing.

Opening up the invitation process does not necessarily mean that Google will let anybody sign up on their own, though. The company keeps the Google+ population growing slowly, making spams less possible.

 

 

In terms of member base, the newborn social network still cannot compete with Facebook. While Facebook has hundreds of millions of members, Google+ reportedly has millions, said Eric Schmidt, the executive chairman of Google.

However, Paul Allen, the founder of Ancestry.com, noted that he is very surprised at how fast the userbase is growing. Based on census data and surname frequency, he estimated Google+'s membership as 1.7 million last week, but expected the figure to rise to 4.7 million today.