VMWARE: vSphere Pricing, Packaging and Licensing Overview whitepaper
VMware vSphereTM is the most complete and robust virtualization platform on the market today for building cloud infrastructures. The pricing, packaging and licensing schema for VMware vSphere 4.1 is designed to simplify the experience of buying, deploying and managing VMware products. Several changes in VMware vSphere 4.1 provide customers with additional value and flexibility