Citrix and Nimbula have released new versions of their cloud operating system software today, both touting Amazon EC2-style cloud capabilities. These products allow enterprises and service providers to build their own Infrastructure as a Service (IaaS) offerings like EC2. Nimbula Director 2.0 supports VMware’s ESXi hypervisor and Cloud Foundry Platform as a Service and Nimbula has joined VMware’s Technology Appliance Program (TAP). It says it’s software brings “EC2-style cloud” capabilities to VMware customers. Citrix, meanwhile, says CloudStack 3 enables “Amazon-style clouds” but is hypervisor agnostic with support for KVM, OVM, vSphere, Xen and its own XenServer product. Nimbula has a long way to go to catch up with Citrix’s CloudStack 3 adoption in the market. Nimbula Director 2.0 is still in beta and won’t be generally available until March 2012. Citrix claims CloudStack 3 is already powering over $1 billion in revenue for more than 85 large scale production clouds. With so many companies competing in the IaaS platform space, 2012 will see brutal competition and one or two exiting the market.