These are the changes or updates made to VMware Compatibility Guide since it was last published:

• Added support for Windows 7 Enterprise, Professional, Ultimate and Home Premium Editions on ESX 3.5 Update 5
• Added support for Windows Server 2008 R2 Enterprise, Standard, Datacenter, and Web Server Editions on ESX 3.5 Update 5

Check the VMware Compatibility Guide here: http://www.vmware.com/resources/compatibility/search.php?deviceCategory=software&testConfig=16