Thunderbird 11 has been released, this is a new release that comes with a new user interface with Tabs above the main menu bar to facilitate navigation and make it more contextual, fixed a various bugs including security bugs, Thunderbird notifications may not work properly with Growl 1.3 or later, Fixes a crash seen during importing of Microsoft Outlook profiles.
Installation on Ubuntu 11.10 and LinuxMint12
Open terminal and enter the following commands:
sudo add-apt-repository ppa:mozillateam/thunderbird-stable sudo apt-get update sudo apt-get install thunderbird
For other Linux distribution, please download the packages from the Link bellow: