Google+ Hangout !

With the flip of a virtual switch, Google has graduated a popular experimental feature into a standard for Google+ users, the ability to place calls to any number using Google Hangout.

The users will be able, for example, place a voice call from their computers and reach friends or family on their land line or cell phone.The feature is limited to outbound calls and cannot accept incoming calls to your Google+ account. It's also currently desktop-only, and isn't compatible with Google+ on mobile apps.

Calls to phone numbers in the U.S. and Canada are free, and callers can buy credit todial out to international lines.

To place a call, click the "Invite" button in Hangouts, then the "+telephone" link. After entering the number, hit "add." The dialer currently stores one number at a time.

The Google Voice platform powers the entire operation, though the feature bears the Google+ Hangouts name. You can similarly place calls to land lines and mobile phones using Google Voice's integration into Gmail.

Calling out with Hangouts is a third high-profile experimental feature that Google has pulled into the mainstream product, along with screen-sharing and support for Google Docs.