How it works: Man, this is one big feature I've been looking forward to--and I have yet to hear any final confirmation apart from the 300 New Features page that it made the final cut. This new Universal Access ability allows you to monitor a spot on your screen and automate what happens when that spot changes. You can monitor up to 10 different spots--no that's not a joke about leopards--and get alerts when anything happens there.
Who will use it: Anyone into automation, who's waiting for a file to finish downloading, for a batch job to finish, or for a friend to come online. All of these state changes can be grabbed via the visual screen feedback they produce.