I've been considering installing Safari on my Windows machine for a while. Is it worth it? I normally use Opera, and fall back to Firefox, then to IE if I need extra compatibility (not very often) - would Safari add anything to that?
Well, Webkit (the rendering engine behind Safari) is really fast and supports the latest standards. I would use Google Chrome though as it shares a large part of its codebase (including Webkit) with Safari but it is more suitable for Windows. Safari looks really out of place in a Windows environment in my opinion.
I use Safari on Windows about 30-40% of the time (the rest being Firefox). Safari has Apple's font rendering which makes the text look better and more correct from the typography's point of view. See, for example Joel's article on the subject. I find it being significantly easier on the eyes, and I choose Safari for lengthy articles.
On Mac on the other hand, I find myself using Firefox almost exclusively since it's got all the GreaseMonkey goodies and it takes much less CPU than Firefox, which translates to cooler and quieter notebook.