Microsoft has made a HUGE commitment to the cloud. They’ve spent billions of dollars building datacenters around the globe that provide on-demand, dynamically scalable compute, storage, caching and content delivery capabilities. This is Windows Azure.
Azure datacenters are populated with specially-built shipping containers filled with server blades and storage racks. These containers are ordered on demand, delivered to site, plugged into power, network and cooling and then self-integrate into the Azure fabric.
Rather than buying and hosting complex and costly cloud-scale infrastructure, most customers rent compute and storage resources as necessary.
Compute resources come in two flavors: Worker Roles and Web Roles.
Windows Azure worker roles are essentially Windows Server VM's running on racks in Microsoft’s datacenters. Azure Web Roles also run IIS. This means that pretty much any existing Windows Server app can be easily run in the Azure cloud.
Today, Microsoft leaked a new codename: Azure “Antares” (source: Mary Jo Foley @ ZNet):
Details are sketchy at present, but I believe that Antares is a natural evolution of Microsoft’s current web/cloud infrastructure towards a more comprehensive, complete and holistic web/cloud hosting platform, allowing one to build and host a web/cloud app and deploy it seamlessly and without change to in-house servers, servers operated by hosting partners and/or to servers hosted in Azure.
Its highly likely that this infrastructure will integrate current and new features such as FastCGI and IISNode in order to better support sites that use technologies created by open-source communities such as Java, node.js and PHP.
More details as they appear