This was reported on this website:
http://www.g2zero.com/2006/09/examining_de..._the_firef.html
QUOTE
The analysis resulted in 655 defects and 71 potential security vulnerabilities. The Firefox team has been given the analysis results, and they will determine if or how they will deal with the issues.
Only someone with in-depth knowledge and background of the Firefox code could judge the danger of a particular security vulnerability. . .
I'm still more likely to use Firefox than IE (especially the new beta IE).