I searched the Community to find out if domain user account is still needed with vCenter Server v5.1 when SSO is used. Only one close match was this: http://communities.vmware.com/message/1818598#1818598
The hardening guide explains that local account is used within vCenter inventory permissions to restrict Domain Admins and other people in BUILTIN\Administrators group to inherit full admin rights.
But do we really still need any domain accounts (domain user or domain service account) to install and run vCenter application and additional modules if there is SSO module where AD integration is made? Even the vSphere Client connection rely on SSO integration and does not make any direct authentication and/or authorization request to AD (via vCenter / Windows OS) anymore. Have anyone tried to install whole pack (SSO, Inventory Services, vCenter, Update Manager, Log collector etc.) by using one local user account? Do you see any pros/cons by doing that?