Microsoft have moved their Windows Autorun V2.1 [1] (967940) update patch from optional updates to automatic updates.

This is the same patch that was released in last month’s patch Tuesday. When  Windows update is next run, this patch will automatically be selected to apply to your machine. This is more likely to affect home users, as companies should be using group policies to control how USB autorun settings operate.

[1] http://www.microsoft.com/technet/security/advisory/967940.mspx

Chris Mohan --- Internet Storm Center Handler on Duty