Shoutbox

Some features won't be in the initial 4.00 release, but will be added back in the 4.1 or 4.01 release, can't remember which.

Also, as it hasn't been said yet, the background colour of all the windows (ie. preferences, event viewer, etc.) changes colour to correspond to the colour you've set Windows Live Meessenger as. for example, Chris Boulton's screenshots have a blue background, because he obviously has his WLM set on blue, where as mine are green.