Mozilla Messaging released Thunderbird 3 beta 2 for Windows Mac and Linux.
New features and changes are:
New activity manager,new ability to Archive email and bugs fixing.
In brief new activity manager records all interactions between your e-mail provider and Thunderbird, making it far simpler to track down errors when you send or receive mail. There’s also new system for archiving messages based on Gmail’s “archive and forget it” method. The new beta offers the traditional multiple-folder-based solution, as well as the new dumping-ground style, which can be activated via the “A” hot key.

IMAP users now will see Thunderbird download their messages by default in the background. Mozilla looking this as it will  improve offline operations and speed up message loading times.