I am using MS CRM 2011 and have configured the CRM server to allow people to opt-out of mass emails.
I have email tracking enabled; when I reply to an email to unsubscribe the CRM server is not changing the Do Not Allow emails setting.
http://blogs.msdn.com/b/dynamicscrmonline/archive/2009/07/03/auto-unsubscribe-in-crm-online.aspx
It looks like CRM 2011 has the same issue as CRM 4.0; as indicated by this MSDN blog post? Can someone confirm that the unsubscribe feature does not work on CRM 2011? The server is up to date.