Wow, that's a long title;-).
As you probably know I am still developing without administrative privileges on my Windows systems. Even with Visual Studio 2005 Beta 2 it works very well (with knowing a couple of tricks like configuring the Administrative Tools Shortcuts with “Run As”). But since I have installed Windows Server 2003 Service Pack 1 I was not able creating Web Projects as non-admin anymore although I have set the permissions according to the MSDN article. While Visual Studio (2003 and 2005) is able sharing a directory as web directory it cannot configure it as application anymore – therefore I had to do that manually. But know I have found out how (as expected it's one of the Web Servers COM components security configuration) - to solve this issue and get back to the original comfort in combination with staying secure as least-privileged user. All you need to do is the following configuration (not more and not less):
With those two settings you have the necessary permission for calling the DCOM component (IIS WAMREG admin service) which is responsible for configuring IIS.