The latest and greatest update on the Firefox 2.0 branch has been released. This update fixes eight security vulnerabilities including two labeled critical, along with other 100+ stability and performance patches. Users should be getting an auto-update prompt in the next 24-48 hours or can manually update now via Help, Check for Updates…
As a reminder if you are still using Firefox 1.5, Mozilla has ceased support and updates nearly six months ago. Users are strongly encouraged to upgrade to the latest Firefox 2 build. Mac users, there are some known Firefox issues on Leopard.
News Sources:
The Firefox Extension Guru's Blog 
[…] Firefox 2.0.0.8 was Released fixing eight security vulnerabilities and caused several new regressions including some with JAVA and Vista. However unlike Microsoft which would sweep these bugs under the mat by calling them features, Mozilla would address and fix these regressions (and several more) with Firefox 2.0.0.9 […]