Note: this entry has moved.
I've been using FireFox for a while now. It used to be FireBird when I started, and it's been my default browser ever since. But every new version surprises me, as well the constant availability and improvement of all sorts of extensions to it, as well as a growing number of themes to make it look even better.
For example, I stumbled across the Google Toolbar. It even supports features not available in the Google-provided IE toolbar! Amazing. And I can't live anymore without the extensible search functionality:
It has a sleek design, way better than aged IE one:
And there's an absolutely must-have extension that allows me to open those everytime-less-often pages that can only be browsed with IE:
And there's even an ActiveX wrapper that hosts the Gecko rendering engine (the one behind FireFox, Mozilla and Netscape) and that implements all the interfaces of the IE WebBrowser control. This means you can get rid of the buggy-non-standard-old jscript-aged IE browser for your embedded browser needs!
As if it wasn't enough, Mono has a Gecko# project in the works! IE is dead. Way toooo late to make anything useful to it to catch up with the new wave of internet browsers. I sincerely hope all developers start using FireFox, deploying it, and making web apps that leverage the power of the latest W3C standards. For most extranet/intranet applications, you can control the browser. Go fight for any Gecko-based browser. You'll make yourself a big favor by avoiding IE quicks. You'll also contribute in forcing Microsoft to stop toying with the idea that they can control the internet, its content, and the platform through XAML, Avalon and whatever they invent for that purpose. Dynamic and useful websites were largely possible thanks to MS innovation back in the browser wars days. Don't let them abandon that path. It's the one that benefits us all, just as it did by freeing us from the even-more-buggy Netscape Navigator 4.
Update: I forgot to mention the most important thing for newcomers: FireFox setup for Windows is only 4.7 MB!!! That's even less the size that Netscape Navigator 3.04 had (5.53 MB)!!! Compare that with the incredibly huge 77.51 MB of IE6+SP1...
There's an interesting article on the revival of the browsers war on XML.com.