One day after the release of a new (and potentially bogus) study suggesting Google+ activity has decline significantly, the search giant grabbed headlines by announcing that the social network is now open to everyone.

Of course, considering how easy it was to score a Google+ invite, you probably figured it already was open to the public.

In a blog post on Tuesday, Vic Gundotra, Google’s senior vice president of engineering, said:

For the past 12 weeks we’ve been in field trial, and during that time we’ve listened and learned a great deal. We’re nowhere near done, but with the improvements we’ve made so far we’re ready to move from field trial to beta, and introduce our 100th feature: open signups. This way anyone can visit google.com/+, join the project and connect with the people they care about.

The latest improvements include Hangouts on smartphones and tablets (Hangouts is the video-chat feature that lets up to 10 people take part); a new hybrid search that enables users to search within the social network and on the open Web; several Hangout “extras,” and more.

An additional feature that may wind up being the most relevant for PR professionals and journalists is Hangouts On Air. It enables Google+ users to create a Hangout session that anyone can watch. These On Air sessions can also be recorded.

Here's how it works: When you notice that someone has started a Hangout session, you can either join or, if all the spots are taken, opt to watch the hangout, which will be streamed on YouTube. You can read more details on how it works here.

Conceivably, a PR professional could pull nine executives into a Hangout and invite the media (and the public) to watch. The ability to record it means a company can share the video, while reporters can play it back when they reporter their stories.

However, Google plans to roll out the On Air feature slowly.

Gundotra explained:

We’re starting with a limited number of broadcasters, but any member of the Google+ community can tune in. In fact: we’ll be hosting our very first On Air hangout with will.i.am on Wednesday night, September 21. For more information visit will.i.am’s or my profile on Google+.

The will.i.am Hangout could be a sign that Google plans to tap celebrities to help rekindle interest in the site. After its launch in June, more than 20 million people flocked to the site; however, since then activity on the social network has slowed.