I'm beginning to think upgrading to Leopard was a huge mistake. Tonight while watching a dvd on my mac pro, the screen saver activated while in the middle of the movie preempting it. When I hit the space bar, my dock was gone and I had relaunch it by hand. This never happened with Tiger. Aside from that, my mac pro has frozen up twice while running iTunes and Aperture at the same time, and I had to power-cycle the machine to regain control of my desktop. There were no RAM errors, no kernel panics, core dumps, nothing in any of the log files. Just thought I'd air a fresh grievance.