Facebook shut down their XMPP service earlier this year and because of this, Pidgin/libpurple no longer supports Facebook Chat. For those of you who want to use Facebook Chat in Pidgin, there's a new plugin which makes this possible, called purple-facebook.

FBMessenger is a stand-alone Facebook Messenger app for Linux, very similar to the official Messenger for Windows.

This isn't an official Facebook application but it has been created by a Facebook developer and comes with the following features:

Gwibber, the microblogging client available by default in Ubuntu, has been rewritten in QML recently and is now called Friends App. 

Also, Gwibber Service (the backend) and the Gwibber Unity Lens have been replaced with "Friends Service" and Unity Friends Lens and the new packages have landed in the Ubuntu 13.04 Raring Ringtail repositories for a while, but they didn't work properly, at least for me, until a couple of days ago.

Gwibber used to be installed by default in Ubuntu, however, the new Friends App isn't (though the Friends Lens is installed by default) available by default in Raring and I'm not sure if it will make it, but you can easily install it via Ubuntu Software Center. Below you'll find instructions for installing the new Friends App in Ubuntu 12.10 or 13.04.

Facebook doesn't currently work with Gwibber (the Facebook feeds aren't updated - bug HERE) and this bug affects Ubuntu 12.10, 12.04 and probably older Ubuntu versions as well.

Update: This bug also affected Ubuntu 13.04 (currently under development), but a fix was pushed a few minutes after publishing this post. Hopefully the fix will make it into older Ubuntu versions soon.

There is, however, a work-around which I can confirm it works for Ubuntu 12.10 Quantal Quetzal and 12.04 Precise Pangolin - so here's how to apply it and get Facebook to work with Gwibber again!

Firstly, a short introduction of "Lenses" via the Ubuntu wiki: "Lenses used to be known as Places. When referring to code and APIs we still use the term Places, but the user-visible name is Lenses. The Places name will be retired in 11.10".

I've recently came upon a very interesting Unity Lens for Gwibber developed by Ken VanDine and couldn't wait to try it but it didn't really work until the latest Unity update released a few hours ago. You can use the Unity Gwibber Lens to quickly access your Gwibber posts, replies, private messages and so on. And it also comes with a search.