I think things are usually zippier on a clean 10.5 install before all of the updates and apps, but I came across the opposite impression on my TiBook 867. On initial install, Leopard’s graphics /UI handling was noticeably stuttering and occasionally glitching. I thought it could be Spotlight’s indexing to blame so I waited it out and no improvement. I then ran the series of updates 10.5.8 combo and all the security patches and after a reboot it was running buttery smooth as expected. There must have been improvements to the Mobility Radeon 9000 drivers in the updates.