I've been using show() during testing in FF an it worked fine. When it was all working, I did a little cross-browser testing and Safari for Windows has a weird rubberband effect on my show() div (which unfortunately is encased in a <td> tag).
So I tried slideDown()... it works great in FF and Safari! And Opera too! But... IE7, nothing doing. The div shows up but then disappears immediately.
OK, let's try slideUp(). Yes! Works in IE7! Oh... but not FF, Safari, or Opera.
This is getting silly.
Finally I tried fadeIn() and it works on all 4 browsers I'm testing with.
I think this all has something to do with the fact the <div> tag I'm making visible is trapped inside a <td> tag.