Snow Leopard Installed
Took the plunge and installed the latest version of Mac OS X, Snow Leopard, and it went off without a hitch. I had to upgrade three utilities to the latest versions: Snapz Pro X, Default Folder X, and Little Snitch. Apart from that, everything seems to be working beautifully.
Yes, I definitely do notice a speed improvement in many functions. And my startup drive is reporting more than 20G of freed-up space after the installation, which is pretty amazing.
The optimization of Snow Leopard is actually audible. My Mac Pro desktop machine has a fan that changes its speed based on how hard the processor is working; when you launch an application that drives the CPU harder, the fan speeds up and gets louder. But with Snow Leopard installed, it is very noticeably quieter, which means the hamsters in there are working much less.
The whole upgrade process took about an hour, with another 15 minutes to upgrade the Apple Mail database the first time I launched it. All in all, a very smooth and painless upgrade. I highly recommend it to all Intel Mac users (it requires an Intel CPU).
Here’s a helpful Wiki page if you want to check to see if a particular application will work: Mac OS X 10.6 Snow Leopard Compatibility List.