Browser security graphs
The Web browser security summary page now includes graphs showing the relative number and severity of known unpatched security vulnerabilities in time since November 2004 in Internet Explorer, Firefox, and Opera. The graph is updated automatically as time goes on and as new security vulnerabilities are discovered and fixed.
It is interesting to note that, although usage share of Firefox and Opera continue to rise, the number of vulnerabilities seems to be in an overall decline. Meanwhile, the Internet Explorer vulnerability count continues to be on the rise.