I got Leopard a couple of months ago, and I noticed that when viewing videos on the web using Quicktime, the audio works but there's no picture. It worked when i was using Tiger. I downloaded the newest quicktime version for leopard multiple times but it still doesnt work. I'm viewing videos on lots of sites, including the Apple website. i have an iMac running leopard with a 1.83 GHz Intel Core Duo with plenty of hard drive memory space.