IIS is built on an open and modular architecture that allows you customize and add new features through free IIS Extensions.

on the following link here, you can find in the iis.net official site all the IIS extensions in order to install it on you server or local IIS.

The IIS team always adding new features to IIS to help you optimize your website for search, serve media to multiple platforms and devices, deploy web applications, route URL requests and more!

Some of the current extensions are (and of course you can read about them on their site):

1. FTP Publishing Service – content publishing utility that help you do it more securely and easy
2. Web Deployment Tool – This tool simplifies the migration, management and deployment of IIS Web servers, Web applications and Web sites.
3. URL Rewrite - IIS URL Rewrite 2.0 enables Web administrators to create powerful rules to implement URLs that are easier for users to remember and easier for search engines to find.
4. etc…

Hi,

Scott Guthrie revealed these days the IIS Express that comes along the VS 2010 Service Pack 1.

I found very good things and improvements under this SP, but no doubt IIS Express is the best one of all the improvements list.

IIS Express is coming to replace the ASP.NET Development Server that enables you a local (VS env) we application hosting in order to server your ASP.NET code application.

The major improvements are:

• It’s lightweight and easy to install (less than 5Mb download and a quick install)
• It does not require an administrator account to run/debug applications from Visual Studio
• It enables a full web-server feature set – including SSL, URL Rewrite, and other IIS 7.x modules
• It supports and enables the same extensibility model and web.config file settings that IIS 7.x support
• It can be installed side-by-side with the full IIS web server as well as the ASP.NET Development Server (they do not conflict at all)
• It works on Windows XP and higher operating systems – giving you a full IIS 7.x developer feature-set on all Windows OS platforms

My best one is the SSL support improvement. IIS Express enables you to provide an SSL based application and doesn’t ask you to install the SSL certificate because it uses the self signed certificate that comes with the IIS Express setup.

More details here.