With the help of the Facebook Messenger Integration, the users will get a permanent side panel on your browser, even if they don't have Facebook.com open in any of the tabs or window. With the help of this side bar, the users will be able to update their Facebook status, communicate via chats, check notifications and even tag photos/videos.
The Social API of Mozilla Firefox 17 can support other social networking sites as well but so far only Facebook is making most of the same.
The other significant addition in Firefox 17 is the blocking of Click-to-play plugin.
Plugins that are blocked with the click-to-play flag will not load by default, but can be easily activated by users. This gives us a more user-friendly way to warn about plugins that should be updated, that give users better control over their browsing experience.
In this new update, Mozilla has added more than 20 promised performance improvements and has given a face lift to its bar experience, which now has larger icons. However, now Mozilla Firefox is no longer supporting Mac OS X 10.5 (Leopard). One can check out the complete list of improvements here.
Mozilla has also been going bullish on its plans for smartphones. There have been reports, that the company is mulling to launch its first Firefox OS smartphone with ZTE. Several telecom operators including Telefonica, Deutsche Telekom, Etisalat, Smart, Sprint, and Telecom Italia have already pledged their support to the operating system. The first Firefox OS-powered devices are expected to launch commercially in Brazil in early 2013 through Telefonica's commercial brand, Vivo.