Here's some interesting observations from the article:

FIREFOX is a classic overnight success, many years in the making.

Firefox is a Web browser that is fast and filled with features that Microsoft's stodgy Internet Explorer lacks.

Today, it's the Internet Explorer code that is long overdue for a top-to-bottom redesign, one that would treat security as integral, and Firefox is the challenger with new, clean code.

Source: http://www.nytimes.com/2004/12/19/business/yourmoney/19digi.html