What exactly the move is about?
Google website states: "the new Hangouts replaces all other chat solutions, including Google Chat, Google Talk, and Google+ Messenger".
The most complicated part is to understand what is gone, updated or new, because Google has so many different services. Here's my not-comprehensive list of chat-like services:
- Google Talk stand-alone for Windows (binary) - no update
- Google Talk app for Android (binary) - update
- Chat widget in Gmail / Google Apps (web) - update
- Google+ Messenger, a widget in Google+ (web) - update
- Google Chat - part of all services responsible for voice/video (not a product)
Is this move a mandatory or opt-in?
Google explicitly states that it is Opt in for Google Apps, i.e. for organizations. For private users, it is opt in via downloaded update (apps) or agreement popping-up in a web app.
Why does this matter / why should we care?
Community has shared several concerns regarding this:
- Every Google Talk client used to connect to XMPP server which supported XMPP Federation. Hangout clients doesn't.
- XMPP is open-source project, Hangout is proprietary.
- Google used to contribute to XMPP protocol family work by adding peer-to-peer voice and video. Now it will obviously stop.
As you can see, there are both "technical" and "political" concerns here. I'm going to focus on technical issues only in this post.
What is XMPP Federation?
It is a standard feature of XMPP servers that allows server-to-server communication. So, for example if one user connects her XMPP client (say, Trillian) to jabber.org server and another user has Google Talk connected to (obviously) Google server, these users can have each other in friends list and talk to each other. This is possible thanks to the fact that Google and jabber.org servers are federated.
Because Hangout clients are not XMPP, they cannot benefit from federation. After upgrade to Hangout, friends from other IM networks will become unavailable. This is the biggest concern about the move.
P3chat service relies on federation too. P3chat bot that you add as a rooster (aka. friend, buddy) to your Google Talk users list, resides on P3chat XMPP server. That's because P3chat and Google XMPP servers are federated, you can receive messages from web visitors to your Google Talk.
How will this affects P3chat users?
Loss of federation for the clients who upgrade their Google Talk to Hangout, means they cannot chat with visitors of P3chat-powered web sites anymore.
Good news, though, is that most of our clients use Google Talk stand-alone app for Windows, which is not updated. So, for most of us this is not relevant and you don't have to take any steps. If you use Google Apps and you wish to retain the possibility to chat with your customers via P3chat, then please read how to Out out.
I realize this whole matter might be complicated, especially for non-technical users, so feel free to drop us a line at firstname.lastname@example.org in case you have any questions.