Microsoft Exchange Server 2010 SP1 UM Language Packs

Microsoft released Exchange Server 2010 SP1 UM Language Packs, v14.01.0218.015
Download from here

Microsoft Lync 2010: May 2011

Microsoft released Lync 2010, v4.0.7577.280
See description in KB2551268 and download from here x86 or x64

Lync Server Documentation: May 2011

Microsoft updated the Lync Server 2010 Documentation, check here
You can download the compiled version from here

Best Practices for Virtualizing Exchange Server 2010 with Windows Server® 2008 R2 Hyper V™

Microsoft released Best Practices for Virtualizing Exchange Server 2010 with Windows Server® 2008 R2 Hyper V™ document, v1.0.
Download from here

Microsoft Lync Server 2010 Network Monitor Parsers

Microsoft released Microsoft Lync Server 2010 Network Monitor Parsers v3.6, download from here
You can download Microsoft Network Monitor v3.4 here

Microsoft Office Communications Server 2007 R2 Documentation

Microsoft released Microsoft Office Communications Server 2007 R2 Documentation, v1.5.
Download from here

Microsoft Lync 2010 Quick Reference Cards

Microsoft released Microsoft Lync 2010 Quick Reference Cards, v1.0.
Get them all here

Lync Updates Available on Microsoft Update

Now Lync Server and Client updates are now available on Microsoft Update
Se more here