I am a big fan of firefox 4. Its so far a great browser.
What do I want?
Let me put the “super button”, the url/location bar, and the forward & back buttons on the title bar. Let me put the tabs down the left side.
Seriously, if I can put the location bar and such in the title bar, my screen real estate will be more effective. I tried this in FF 4. It crashed when moving the address bar up.
Bigger question – why aren’t vertical tabs at least supported by default in browsers not named Opera? Firefox, Chrome, IE, and so on are three years behind on this one. Give us at least a toggle, darn you!

Be nice with what you write.