I'm on Mac OS 9.2 so I can't use Firefox (until I migrate to OSX), but I've been using Mozilla since Exploder (Exploiter, whadya wanna call it) all of a sudden decided not to work a couple months ago. It neatly and easily imported all my bookmarks from IE, does a much better job of saving passwords & other info, and has a really nifty tab scheme instead of opening new windows.

I love it!

Linn