I started using Mozilla Firefox as my primary browser. It seems to be the best option. Safari is just too buggy has very simple customization options. Mozilla is great, but I don’t need the email or newsreader clients. Too bulky. Camino, the Mozilla option built to take on Safari, suffers from the same “too-simple” problem as Safari.
Firefox has a ton of customizations and controls. You can use almost any Mozilla extension, which means a ton of Web development tools. The only major problem with Firefox is that Shockwave doesn’t work in it. As far as I can tell, it is not that Shockwave doesn’t work, but that there is no way to install Shockwave. So it will hopefully be fixed in the next version. This would be a trivial problem for most people, but as a Shockwave developer, it is quite a big deal. My computer is dripping with irony at my choice. But Safari launches quick and easy when I need to view Shockwave content.
One of the best features of Firefox is the extension “Web Developer” (http://www.chrispederick.com/work/firefox/webdeveloper/). It gives you all sorts of tools that help to debug HTML rendering issues and such. I also found a tool that allows me to edit the CSS of any page on the fly. Nice for tweaking my pages or seeing how others do their CSS.