Introducing IIS Express - ScottGu's Blog

IIS Express combines the best characteristics of IIS7 and Cassini, and will make it easier to build and run ASP.NET sites and applications.

IIS Express will work with VS 2010 and Visual Web Developer 2010 Express, will run on Windows XP and higher systems, does not require an administrator account, and does not require any code changes to use. You will be able to take advantage of it with all types of ASP.NET applications, and it enables you to develop using a full IIS 7.x feature-set.