New build of Firefox, Seamonkey and Thunderbird released..
As we know, the gang behind Firefox don't release security updates, they release entire new builds of their Web browser.
A new build has been released - 1.5.0.5 which addresses numerous vulnerabilities - 7 of which are classed as "critical":
http://www.mozilla.org/projects/security/known-vulnerabilities.html#firefox1.5.0.5
You can download the new build here:
http://www.mozilla.com/firefox/