Choose one of the web frameworks RoR, web.py or Cappuccino and write something cool on your own. Something small enough to show your future employers that you can write good software. It would help you to make the transition and also gives companies confidence that you are capable of making this career change.
Your could write your own blog, since your were in QA something related to that like a web application to view continious integration status or test results, a web app to show what web 2.0 sites are up or down.
Write down a few requirements for what you plan to do if you end up having more than 10 requirements for the project choose another.
