KB 969690 - We have fixed the bug introduced in Update Rollup 7 which caused the sender of the Delivery Status Notification (DSN) to be unresolved.
Disable kernel mode authentication in Windows Server 2008 for CAS servers - As documented here, it was required to manually take the additional step to configure the CAS servers running Windows Server 2008 to disable kernel mode authentication. Starting this rollup, the installer will configure this for you.
X-Header promotion to named properties- Change to the way X-headers are promoted to named properties. More on this in Jason Nelson's blog post Named Properties, X-Headers, and You.
KB 961606 - We have fixed a bug where Outlook Web Access (OWA) users may find that the font size of plain text messages is extremely small on third-party Web browsers.