I had the following issue so I thought I'd blog about it:
When hitting Ctrl-F5 in Visual Studio 2005/2008 to run a web application in Vista, the Development Server gets started, Internet Explorer opens but nothing happens, although the web application is set to run with Development Server, ASP, ISS and everything required is installed.
Go to c:\Windows\System32\drivers\etc\ and open the file named hosts with a text editor
Search for the line containing "::1" mapped to "localhost"
Change "::1" to ":::1" by adding an extra ":"
Save the file and everything should be running fine