I read the 'Tech and You' column in Business Week the other night, and the columnist (IIRC, also a columnist for the Wall Street Journal) advised readers to install and use either Mozilla Firefox or Opera...anything you like as long as it is not IE, unless required for a specific application. The columnist pointed out the numerous security holes in IE: patched, yet to be patched, and yet to be discovered. He surmises that IE won't be fully patched for the moment until WXP SP2, but that omits an awful lot of users out there in Userlandia.
There are many, many people who haven't and won't upgrade from W98, W2K or even WNT to WXP. Some of these are home users, a lot of these are schools or not-for-profits, and there are many businesses who can't make the business case for Billg's Xtra Profits operating system and the accompanying hardware that may be needed in their organizations. (I've been there; I know...)
I've paid for Opera since v3.2, and it remains one of my favorite browsers, although it chokes on a fair number of pages, as do numerous flavors of Mozilla/Netscape. I use IE for JU, since JU requires IE for most of its' features. You can't post more than one article/day unless you use IE. There appear to be other functions tied to IE, but that's the only one I can definitely prove to be true.
I admit to my share of Borgitude, possessing MCSA:Messaging (English translation "one exam short of MCSE W2K"), but IMHO, a browser does not, never has, and never will constitute "part of an operating system". It should not be necessary to bring up a specific browser's window within WinFoo to display help screens, perform administrative tasks, run any kinds of consoles, etc. If a browser is required, any browser should function exactly the same as another. All code that is used to display help screens, perform administrative tasks, run consoles, etc. should use IETF/W3C standards, and not manipulated to require any particular browser. The code should run exactly the same in Mozilla, Netscape, or Opera as it does in IE. However, I stand a chance of becoming President of the United States sooner than this happening.
Let the flame wars begin...