It won't probably be any faster at number crunching or encoding tasks, but UI speed and flow is unbelievable! With only 768 MB RAM Leopard delivers absolutely instant UI experience anywhere. That's what I wanted my user interface to be like ever since BeOS! Even my 3Ghz 2 GB RAM Vista PC still has to access the hard disk sometimes when popping up the start menu or windows. As if this couldn't be done better in times of Ghz machines.............. Nothing, not a fraction of a second lag anywhere with Leopard. Even much better than Tiger, which was also fast, but at least on old machines you had sometimes to wait a second for a folder's contents to appear (like "Utilities" when you hadn't used it for a long time). Additionally Safari 3 is the fastest browser I have ever used (page rendering speed). Again faster than Firefox on my 3 Ghz machine. Safari stutters a little bit while scrolling though, that must be fixed. It didn't do that on Tiger. All this on top of this gorgeous looking UI... Great work, Apple!