I know you said quality center, but Janova is a new web-based automated testing tool that is based on agile methodology. Janova is based in the cloud and does all coding behind the scenes, so that BAs can set up requirements in the tool, and even set up the tests themselves. The requirements become the tests in Janova, and it is designed around use-cases in a user-friendly method. I would recommend checking out
www.janova.us for a free trial. You can currently get 30-days free of an enterprise accounts (unlimited applications, multiple admins, multiple users).
