I've been using Firefox for a long time now...longer than I remember, and before that I was using other NON-IE browsers. Why? Because of the security issues that IE. With the appearance of Firefox and it´s cool features, and more importantly support for plugins, it grew on me. However, I've always had to launch IE because some sites just wouldn't work. It's not Firefox's fault, it's the site's fault. It's not designed to work with browsers other than Internet Explorer. Some of these sites I use frequently, such as online banking, and now recently Sharepoint and Microsoft Exchange Web Access. Things just don't work.
I've put up with it until today. I finally uninstalled Firefox. I made the terrible mistake of installing Firefox 3.0 a couple of weeks back when it was released and I must say, I'm very disappointed. Great looking skin, but in terms of stability, it's just not there. I get at least 10 crashes a day and I'm just tired of it. So for now I've gone back to IE 7 which is decent enough, and although I'll miss many of Firefox's features, at least I don't lose time or work.
Maybe someday...