I've decided to try Firefox as my default browser for a while.  I like the idea of tabbed browsing since it keeps my task bar uncluttered, but I'm so used to Alt-Tab to switch between windows that I might get frustrated with it (you can use Ctrl-Tab to cycle through tabs, by the way).  I believe Firefox users will enjoy a period of rest from spyware until the scum who develop the stuff decide to focus their energy on exploiting other browsers like Firefox and Opera.  However, that may depend on how successful Firefox is in gaining a significant share of the browser market.

One of the first things I noticed was that the menus on my Web sites didn't work quite the same in Firefox.  Instead of the mouse pointer turning into a hand when placed over the menu, it would look like the I-beam used to select text.  Apparently, in CSS you must use the following, and the order does matter.

.someCssClass { cursor: pointer; cursor: hand; }

Firefox recognizes "pointer" where IE uses "hand."  If you reverse the order, then IE won't work correctly.