3 Minute View on Vista: Tablet PC Input Panel
This screencast covers what all tablet pc users will be using in Windows Vista - the Tablet Input Panel. One of the great features is the way that it is "context sensitive" which means that whichever application you are running, if you need to enter text, you can do so with your tablet pen.
It's also really cool how it's hiding just off screen ready to fly out whenever you need it.