Here are some samples of some basic javascript transition effects.  We are thinking about putting some of these nifty effects into certain areas of .geographical media.  It seems to be rather trendy these days to do so. 

I have created the following effects: Fade In, Fade Out, Fly Out and Drop Out, Drop Back

The effects are all very easy to do with Javascript adjusting the style properties of the object you wish to have the effect on.  I found the opacity properties here at quirksmode  http://www.quirksmode.org/js/opacity.html .  I consider quirksmode to be the best source of well tested solutions to some of the more complex aspects of javascript programming.  I've used his work often and would recommend his site to anyone.

Here are the sample effects:

http://joshua.perina.com/transition-effects

I'll write more and explain the code once I've cleaned it up a bit.  At the moment it's just 1/2 hour quick prototype.