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Makes sense to me, but I'm confused by one thing.

"Every single feature he mentions, Windows to Go, Direct Access, and side-loading of Windows 8 apps [on RT tablets; x86 Windows devices won't need it] requires Software Assurance on the OS."

I thought SA was used to basically pay extra now for upgrade rights when a new version came out. Why would this have any effect on using those features? Also, does that mean that a non-RT Windows 8 device 'without SA on the OS' wouldn't be able to use those features?