16 vulnerabilites for Firefox vs. 80 vulnerabilities for IE...Firefox is sure going the way of IE... - sarcasm. Microsoft publishes 8 security fixes at a time!
The numbers you cite are TOTALS of PATCHED and unpatched vulnerabilities discovered so far for browsers of DIFFERING ages.
The Secunia security service lists as UNPATCHED 19 of 80 threats for the several-YEAR-old Internet Explorer 6.x, 5 of 16 for the several-MONTH-old Firefox 1.x, and 0 of 0 for the serveral-WEEK-old Opera 8.x.