Mike Nash just published information about the ActiveX fix on the MSRC blog. The most important part is:

  1. New machines that ship with Windows will include the ActiveX change. 
  2. For our April IE cumulative security update, we will include the IE ActiveX change in the security update, but we will create a “compatibility patch” (deployed like a hotfix) that allows customers to turn off the change for a limited period of time through the June update cycle (2nd Tuesday in June) to provide time for enterprise customers to resolve compatibility issuess. 

Read more at: http://blogs.technet.com/msrc/archive/2006/03/29/423560.aspx

 

Roger