Mozilla released Firefox 4 Beta 4 with two new features: Sync and Panorama(previously known as Tab Candy).
Out of the two features, Sync is the most important and very useful feature. It lets you synchronize bookmarks, passwords, form fill data, Awesome Bar, history and opened tabs across the computers and iPhone(if you are using Firefox Home App). Google Chrome and Opera browsers already have this feature for a long time. Firefox is playing a catch up, but it’s a much required one.
Panorama, the new name of Tab Candy, is the second feature introduced in this beta. It lets you to organize and group your tabs. Mozilla says
If you juggle many open tabs for work, shopping, music, social sites, vacation planning and more, you can easily group and prioritize those tabs any way you want. With one keystroke you can see an overview of all tabs to quickly locate and switch between tabs or groups of tabs.
As it’s an eye candy better to see it in action rather than reading about it. Check this embedded video