Referenencing the firefox thread that was going on earlier, I ran across this article:
http://www.securityfocus.com/archive/1/378632
that concludes " It appears that the overall quality of code, and more importantly, the
amount of QA, on various browsers touted as "secure", is not up to par
with MSIE; the type of a test I performed requires no human interaction
and involves nearly no effort. Only MSIE appears to be able to
consistently handle [*] malformed input well, suggesting this is the
only program that underwent rudimentary security QA testing with a
similar fuzz utility."
FYI,
Brett