Google+ Hangouts is one of the best, free, group video chat apps we've ever seen. Now, the collaborative, multi-person video calling service is coming to all Gmail users.
In addition to chatting with up to nine people at once, Gmail users will be able to collaborate on Google documents, share screens and watch YouTube videos together. It's a full-featured web conferencing solution — now directly accessed in Gmail. Also, it won't matter if users are on Gmail or Google+ on their computers or on mobile phones. Hangouts replace Gmail's previous video chat feature and will roll out over the next few weeks.
Video chat face-to-face-to-face with Hangouts in Gmail [Official Gmail Blog]