When trying to install Snow Leopard, some people are having a problem where the installer will not recognize the current boot drive as a valid destination for Snow Leopard. Instead, it will display the drive with a yellow triangle on it, indicating something is wrong with that drive. When the drive is selected, the installer claims the system cannot boot from the drive. From cnet.There's more about the issue here. Once I upgraded, I found out that when you upgrade OS X, you have to install all your MacPorts from scratch. Hence, I didn't get much work done today. On the bright side, I really like one of the new backgrounds! ;)
I'm thinking of trading my MacBook on Craigslist for an IBM Thinkpad T61p.