Firefox v. IE8 - which is better?

Just to show that it's not biased, PC World has an article today comparing Firefox with Internet Explorer 8. It's a well-reasoned article, in which the author tends to come down on the side of IE8, although acknowledging Firefox has advantages in some areas, and admitting he runs both every day. One thing the article does not mention - and one of the biggest selling points for me - is the huge range of add-ons that have been written for Firefox by open-source developers all around the world. This is something that Microsoft cannot hope to emulate. It's a strange reversal of the Microsoft v. Macintosh battle. One of the strengths of Windows is the immense range of third party software that has been written for it for which there is no equivalent in the Apple world. If these third-party programs are helping to keep Microsoft well in front, surely the same is true for Firefox?