In their defense...
My issue with IE is it cannot be removed from a Windows machine, it's so tightly integrated you simple are not able to remove it without borking the entire system. Can I remove Firefox from my linux box? An easy peasy one line command.
And as for everyone bleating about how you cannot get a browser without having a browser in the first place there are other ways of doing it - I could imagine a small app using wget that gives you a choice of browser installers to fetch. It's ugly, but it's possible.
Personally I think it's MS's right to include their browser on their OS and I think it's daft if they should be forced to include any competitors software, but they world would be a better place if:
a) the OS didn't depend on the browser for critical functions, eg Windows Update
b) a user could remove IE if they wanted to
c) MS got with the program and starting supporting the current standards rather than making their own ones