VMware vCenter 5.1 implemented a new security feature, Single Sign-On (SSO), that uses the Security Assertion Markup Language (SAML) to exchange security tokens. This combats an extremely well-known and prevalent attack within the virtualization management trust zones: SSL Man-in-the-Middle (MiTM) attacks. However, vCenter still supports the old SSL methods as well to maintain backwards compatibility and to allow management when SSO is not in use. Does this new feature change how we look at virtualization and cloud management security best practices? Is it a launch point for implementing other authentication techniques?