Google has opened up Google+ to all after field-testing it for 12 weeks and has rolled out a raft of features to challenge Facebook's domination of social media.

Google+ has attracted heavy Web traffic, unnerving the world’s most populous online social network, Facebook, which has a user base of more than 750 million.

With the graduation of Google+ from field test to beta, the social network has come up with nine improvements, which includes improved Hangouts and search.

Google’s Hangout is a business tool that allows 10 people at once to hold a meeting for free in the same browser-based video chat session. With the Hangout On Air, users can broadcast and record their session. Google has also added screen sharing, sketchpad for group doodling called Hangouts to create public Hangouts over a certain topic and the ability to create Google Docs from Hangouts. Google+ allows users to access Hangouts on cellphones running on Android 2.3+ devices and the company promises it will soon come in iOS devices.

Facebook is not as business-oriented yet, even with the launch of the Skype-partnered video calling. Facebook video chat comes for free only if you are chatting one-to-one. For chatting in groups, Skype charges extra.

Google+ has search capabilities to let users search and find interesting topics, posts and other information from the Web. By typing in what the user is looking for in the Google search bar, he can see the relevant search results. Getting publicity for a post becomes easier with Google+ with search engine optimization to increase the ranking on Google searches, search engine marketing keyword ads to drive traffic and on-site advertising solutions ranging from AdSense to DoubleClick. Integration the whole gamut of Google services becomes easier with Google+.

Can you start to see/imagine what Google+ does for Gmail? Picassa? Youtube? Not to mention search? The +1 system that Google now has control of (unlike Facebook Likes) can really influence and change the nature of their search, said MySpace founder Tom Anderson.

With the launch of Google+, Google has established a more advanced network than Facebook's with the concept of Circles, which let users make their posts accessible to the circle of contacts of their choosing. When compared to Facebook, it has a private platform that makes the contents available only friends.