One caveat I would add with Firefox is to realize that some of its best features are in the form of Extensions. Once you've installed it, and maybe played around with it for a few days, go to the Extension site and see what else it can do. AdBlock does about what you'd expect. ForecastFox shows me the forecast and current conditions. I have a clock down in my statusbar, since I keep the Windows Toolbar hidden all the time.
Firefox by itself is still a great browser, but be aware that some of the coolest features you can download separately.
