I had some time lately to get my hands dirty with .Net 2008 . The tool as described works under the http layer. So it’s designed to test hard core web functionalities. The tool is not a good choice when it comes to creating verification points and verification of JavaScript client side actions details.

• The tool could be used to verify the core functionality (Not the UI) of the Web application. For example if you have a web application which is notorious for crashes. This tool is so perfect for detecting this whenever a new release is out.

• Recording and playback is so easy and stable.
  

• System requirements are relatively acceptable if compared with other tools. My machine is 2GB in memory. The tool is running smoothly on it.

• Playback only displays actions that are associated with Http requests. It will not display javascript user actions. However those actions can be simulated using coding. Click Microsoft Web Test Authoring and Debugging Techniques article for details.
  

• Only VB and C# coding are supported.
  

This tool may not give you all what we need, but it has some great features for web application functional testing.

The following article is a great resource:

http://msdn2.microsoft.com/en-us/library/ms364082(VS.80).aspx