Exchange team has released Hosting and Multi-Tenancy Guidance for Exchange Server 2013 document. It is available for download here.

Read the complete blog at http://blogs.technet.com/b/exchange/archive/2013/02/20/hosting-and-multi-tenancy-guidance-for-exchange-server-2013-now-available.aspx

Read my favorites blogs:

Designing a backup less Exchange 2010 Architecture

Step by step guide for upgrading Active Directory from Microsoft Windows 2003 to Microsoft Windows Server 2008

Microsoft Exchange 2010 CAS Array – Steps and Recommendations

Appear Offline in Microsoft Office Communicator Server 2007

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Microsoft Exchange Server 2010 Disaster Recovery

Microsoft Exchange Server 2010 Upgrade Guide