Gartner Magic Quadrant: IaaS (CESI)
It is worth mentioning that Gartner makes an important distinction when speaking to the subject of IaaS--CESI (Cloud-Enabled System Infrastructure). The gist of CESI is that cloud services are provide as a "self service" offering. I'd like to take it step further and add, "full provisioning services and configuration without the need for any other humans but the customer." The providers listed below provide CESI capabilities.