I am part-way through an excellent video at
http://www.pluralsight.com/training/Courses/TableOfContents/selenium on Automated Web Testing with Selenium
So far everything I have seen leads me to consider that this is an excellent demonstration of Selenium and I recommend to all ASP.NET developers who want to be able to automate testing of their web pages.
Selenium is a free tool you can download from
http://seleniumhq.org/download/