Update Rollup 3 for Exchange Server 2007 Service Pack 3

Microsoft has released Update Rollup 3 for Exchange Server 2007 Service Pack 3
See info about the update in KB2492691 and download from here

Update Rollup 3 for Exchange Server 2010 Service Pack 1

Microsoft has released Update Rollup 3 for Exchange Server 2010 Service Pack 1
See info about the update in KB2492690 and download from here

Lync Server Documentation Update

Microsoft has updated the Lync Server 20101 Documentation - March 2011
You can see it here, or download the compiled help file of all technical content here

Lync Server 2010, Stress and Performance Tool

Microsoft has released the Lync Server 2010 - Stress and Performance Tool, v4.0.7577.120
You can get it here

Running Microsoft Office Communications Server 2007 R2 in a Virtualized Topology

Microsoft has released the Running Microsoft Office Communications Server 2007 R2 in a Virtualized Topology document - March 2011
You can get i here

Microsoft Lync Server 2010 Capacity Calculator

Microsoft has released the Microsoft Lync Server 2010 Capacity Calculator - March 2011
You can get i here

Procedures for Performing a Disaster Recovery Failover in Office Communications Server 2007 R2 Group Chat Server

Microsoft has released the Procedures for Performing a Disaster Recovery Failover in Office Communications Server 2007 R2 Group Chat Server document - February 2011
You can get i here