We got an article out for a new feature in Operations Manager 2007 R2 CU3 that allows you to pick up a piece of information from the body of one request and then use it to replace a parameter in other requests in a web application.  This is a very significant feature since there were applications that you really couldn’t monitor because they require data in their query strings that are dynamically created.  You have no way of knowing what their value is going to be until the first request runs.  Since the Web Application template had no way of doing that, you were left writing a custom script.  Now you can record or manually create the web application and then modify the requests to perform exactly this functionality.  Details and a sample walkthrough in the article - http://technet.microsoft.com/en-us/library/gg494976.aspx.