I installed it last Wednesday. My first upgrade attempt failed, so I paid a visit to the Tyson’s Corner Apple Store to get some help from the Genius Bar. Apparently the DVD wasn’t clean or something (since the guy cleaned it off), because when I tried archive+install as recommended, there were no problems. The next day, I picked up a 1TB Western Digital MyBook Home Edition at MicroCenter for $220 + tax so the Time Machine feature would have plenty of room to operate. It’s definitely as cool as advertised. I was impressed that when you plug in an unformatted drive, Leopard asks if you want to use for Time Machine. I was pretty lax about my backups before, so this will be a huge help.