With the launch today of Hyper-V - available only in x64 versions - I thought that now would be a good time to revisit the topic of "64-bitness." While it may take a while for client computing to reach the stage where 64-bit is the norm and 32-bit the exception, that day is coming soon for servers - and it may be today.  A few quick facts:

• x64 processors have been with us for over 5 years now.
• While I confess I can’t read every single web page on the AMD, Intel, HP, IBM, and Dell sites, last time I checked all currently shipping servers from major OEMs - and obviously the processors in them - were 64-bit.
• Microsoft announced several years ago that Windows Server 2008 would be the last server OS available in 32-bit. (And let’s not overlook the word “server” there!  I’m not talking about the desktop.)  Windows Server 2008 R2 will be 64-bit only.
• The last time I checked our evaluation download figures, more than half of the downloads were of the x64 edition of Windows Server 2008.
• The virtualization features of today’s processors require 64-bit.

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