We've recently released a new Power Tool to enable profiling of JScript code running in a web browser.  Today getting a good understand on where all of the time spent in the overall user experience in a sophisticated web application is difficult.  This tool shines a light on a key component of overall user responsiveness and does it in a novel way.  It works by running on the server and instrumenting JScript code that is sent to the client so that it reports timings back to the server.  This means you don't have to have control of the clients and you can use the same technique with many different browsers.  It also means you can use it diagnostically in a real running system to investigate why users are complaining about performance of an application.  We're hoping the get some feedback on this approach to help us decide whether/when to incorporate this technology into a future product offering.

Check it out and let us know what you think: http://code.msdn.microsoft.com/AjaxView

Brian