...And regarding Gecko/Mozilla-based browsers on the Mac, Camino is more popular than Firefox. It's been around longer, and it uses a Mac OS X-standard interface instead of that XUL nonsense that Firefox hasn't shrugged off. So form elements on web pages actually look and function like OS X form elements instead of Windows ones being "faked" on the Mac... It does make a difference.
http://www.mozilla.org/products/camino/

Some people still prefer Camino, but I find Safari to be "snappier."