Google Hangout version has started to roll-out for quite a few people yesterday. The most interesting and visually captivating part of this update is the quick reply from the heads up notification and or the notification shade.
If you have been following the development of Hangout, back in December it was rumored that Hangout would have quick reply from the notification shade as well as quick reply from the heads up notification.
You'll also notice that you can now create shortcut of conversations on the home screen. Every little bit to be more productive.
We've also read the rumor that Google would do away with SMS within Hangout. This might be something that's coming in a future update as for now Google is making recommendation within Hangout about switching to Google Messenger.