Ok, so I'm impressed.

By default, Snow Leopard boots into 32 bit mode. Even in 32 bit mode you get a "lessons learned" bump in performance using Apple's latest OS. Where it really stands out is running it in 64 bit mode! I really noticed a difference when booting in 64 bit mode.

To verify that you are running in 64 bit mode, open About This Mac as demonstrated in the picture below.



If you are NOT, then you can try 64 bit mode by rebooting your Mac and holding down the 6 and 4 keys as it boots. If you've booted in 64 bit mode, and all of your software is working well, then you can change your system to default boot in 64 bit mode.

Open the file : /Library/Preferences/SystemConfiguration/com.apple.Boot.plist

Change it as demonstrated in the picture above.

Reboot. Your Mac will now default boot in 64 bit mode without holding down the 6 and 4 keys.

Especially doing graphics editing, you'll notice that your Mac is over 30% faster running in 64 bit mode. If you do decide to run in 64 bit mode, you should buy as much memory as you can cram in your Mac.

I've tested Purify on Snow Leopard in 64 bit mode, and on Windows 7 in 64 bit mode, and it works like a champ!

Thanks for that, Jeff!

Is it only for the Server, though - as this article implies?

Or is it guaranteed for workstations too?

Guaranteed for workstations too! I just did this on my MacBook Pro, going from Leopard, to Snow Leopard, exercising all of the steps in my description.

How does this work out if I have apps that are 32-bit only? Will I have conflicts with software that run in different modes?

The apps should work fine. The thing that may give you headaches are 32 bit drivers. You can put your toes in and test the water by doing the 6 4 key press on boot up to see if everything works. I was lucky, and all of my stuff worked with no problems.