2011 has been a transformative year for Mozilla and Firefox, perhaps the most eventful since launch. No more big, disruptive changes are planned for this year, but that doesn't mean that things will go quiet or that things will slow down.Mozilla has listed some of the things it's focusing on this year, most of which it has already started to work on.
Add-on compatibility is a big concern. Starting with Firefox 10, add-ons are labeled as being compatible and therefore available to install by default and only add-ons known not to work are marked as incompatible.
This should mostly eliminate the problem of users staying with older versions of Firefox so they don't lose their favorite add-ons.
Following that theme, Firefox 11 introduced add-on sync, meaning that add-ons now follow users around no matter where they're working. Firefox can already sync bookmarks, history items and so on.
Another major focus for Mozilla, something it's been working on for a while now, are silent updates. Ideally, new versions of Firefox would be downloaded in the background installed and ready to go without the users even noticing. Some steps have been made in this direction, but there is stikll work to be done.
Finally, the developer tools that have begun taking shape will continue to be expanded. Firefox 11 introduced a new fully-fledged stylesheet editor as well as a WebGL-powered 3D view for the page inspector.
Of course, Mozilla engineers are already working on plenty more features, big and small, but the ones you see above represent some of the larger trends for Firefox.
Even more though is planned under the hood, one of Mozilla's big goals is to advance the web and to do with with open standards. It's working on several cutting edge technologies to ensure that web apps can become increasingly powerful and useful.