Firefox 3.6.11 has been released for direct download although the final build release notes and such like have yet to be updated. The Firefox client will auto-update once the official release goes live later today. The new build contains a number of bug fixes and security fixes and is well worth upgrading to if you use Firefox as your main browser.
In the meantime the large changelog can be found here: https://bugzilla.mozilla.org/buglist.cgi?quicksearch=ALL%20status1.9.2%3A.11-fixed
Mozilla have also released the final version of Thunderbird 3.1.5 their free e-mail client.
"As part of Mozilla Messagings ongoing security and stability update process, we strongly recommend that all Thunderbird users upgrade to these releases. If you already have Thunderbird 3.1 or 3.0, you will receive an automated update notification within 24 to 48 hours. You can also manually fetch this update by selecting "Check for Updates..." from the Help menu."
For a list of changes and more information, check out the Thunderbird 3.1.5 release notes
Download: Firefox 3.6.11
Download: Thunderbird 3.1.5