A new version of Firefox has been released and should be applied promptly to address security concerns. Most folks should Autoupdate without issues (and users can also select HELP and CHECK FOR UPDATES from the Menu bar)
Firefox 2.0.0.4 Released - Security and Improved Vista Support
http://isc.sans.org/diary.html?storyid=2891
What's New in Firefox 2.0.0.4
Release Date: May 30, 2007
http://www.mozilla.com/en-US/firefox/2.0.0.4/releasenotes/
1. Security Update
2. Windows Vista Support: More enhancements and fixes for Windows Vista are included.
3. New Languages: Afrikaans (af) and Belarusian (be) are now available. Beta releases for several new languages are also available for testing.
Security Update: The following security issues have been fixed.
http://www.mozilla.org/projects/security/known-vulnerabilities.html#firefox2.0.0.4
Fixed in Firefox 2.0.0.4
MFSA 2007-17 XUL Popup Spoofing
MFSA 2007-16 XSS using addEventListener
MFSA 2007-14 Path Abuse in Cookies
MFSA 2007-13 Persistent Autocomplete Denial of Service
MFSA 2007-12 Crashes with evidence of memory corruption (rv:1.8.0.12/1.8.1.4)