In light of Chrome's "DRM for web pages" proposal, let me just say that I've been using Firefox exclusively (mostly Nightly) for years. It's gotten really good. The devtools are great, the performance keeps getting better, excellent spec compliance. I really recommend checking it out.
My name is Arne Brasseur and I wholeheartedly endorse Firefox.
@plexus would love to, but the abnormally large design of tabs irks me the wrong way, and Firefox no longer has themes that change that, instead they now have something more akin to skins, not real themes they used to.