The 'Threshhold updates' are a collection of updates for windows 8.1. Some are saying that this is windows 8.2 but see for yourself:
Reference:
http://winsupersite.com/windows-8/further-changes-coming-windows-threshold
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Hello --
As per our usual cadence, today we’re releasing our advance notification for this month’s security bulletin release, which is scheduled for Tuesday, July 10. The July release includes nine bulletins addressing 16 vulnerabilities in Microsoft Windows, Microsoft Office...
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