I've been using Leopard for about a week now and feel that this is the most fluid updates of all the Apple operating systems. I'm not sure how user friendly Time Machine and Spaces will be for most users, I do love the new features of Preview, Email, and ical. Plus, the dock looks so cool!! I would love to hear any thoughts regarding this latest OS, especially regarding Leopard Server. Apple will be hosting some training for this very soon, click here for more details/locations.