Perhaps most of you have heard of and/or use this program, but I wanted to bring it to your attention if not. It's called Secunia PSI. I use it to make sure all of my software is kept current and all of the security fixes are in place. It's free and works exceptionally well. It even offers a "one click" solution for fixes. Just thought I would pass it on for what it's worth.
From their website:
The Secunia PSI is a FREE security tool designed to detect vulnerable and out-dated programs and plug-ins which expose your PC to attacks. Attacks exploiting vulnerable programs and plug-ins are rarely blocked by traditional anti-virus and are therefore increasingly "popular" among criminals.
http://secunia.com/vulnerability_scanning/personal/