I've come across something strange. I bought Leopard when it first released with 10.5 to update my MacBook. I just bought a MBP last week and used my Time Machine backup from the MB to use on the MBP. I had some very minute issues but it bugged me so I wanted to do an erase and install on the MBP. I popped in my Leopard DVD (I know, I know) and instead of the installer coming up, the display went dark. I could see installer but the display wasn't "lit". I then put in the Install Disc that came with the MBP and it worked fine (the disc is 10.5.2). So, I'm assuming there aren't drivers for the newer MBPs on earlier releases of Leopard. This can be a problem if someone buys Leopard over eBay or another site as now the new MacBooks have completely different display drivers.