This paper provides network architects and decision makers with guidance for moving from GbE to 10GbE networking in their virtualized data centers. It begins with a review of the current state of the typical virtualized data center and discusses some of the challenges and opportunities associated with maximizing the value of virtualization. Next, it explores the factors that underlie the excessive complexity associated with GbE networking and describes how 10GbE can address that complexity. It then provides some best practices for achieving optimal networking results in virtual infrastructures. Finally, it addresses some concerns decision makers might have with regard to security and performance.