The good No client access licences required Simple one-size-fits-all licensing Extremely easy to manage The bad Poor web-based mail user interface Push notification of email to iPhone and iChat voice calls from Windows devices didn't work in our tests Launched in August and compatible with all the Intel-based Macs, Apple's Snow Leopard Server is a full 64-bit server OS: for the first time in OS X's history, the kernel, the apps and the drivers are all 64-bit software. This makes for better performance on the same hardware, and Apple has produced an impressive set of benchmark to prove it. But for most people, server performance is not the key issue, and Snow Leopard Server considerably increases the list of things you can do

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Snow Leopard Server