• Installation is faster than traditional OS installs. A lot of it is preloaded to HD during the initial phase - unlike previous versions of OS X the Snow Leopard installer is meant to run from your prior OS and do the preload.
• Total installation time - about 45 minutes. That included the preload phase.
• Boot time is faster, probably about 20-25% subjectively.
• Safari is fast in 64-bit mode. Unfortunately, right now the Safari AdBlock plugin doesn't work in 64-bit, only 32-bit. That slows it down a little and ditches some of the crashproofing that you get from the 64-bit version.
• Time Machine is way faster to a Time Capsule, and the status messages are more informative.
• Useful wake-from-sleep is quicker. Re-acquiring Airport signal is faster as well.
• Launch times on most applications are faster.
• I already know about this, but Kerio Mail Server does not work properly with iCal's CalDAV support. It's not Kerio's fault, but they expect to deal with it themselves in a minor update due in the next few days.
• Cisco VPN support could come in handy. Be nice to see CheckPoint added down the road as well (hint).
