UPDATE: The Webcarzz beta is now available for you to try out! From the team:
I wanted to let you know that you can post the link to http://beta.webcarzz.com on your blog anytime you’d like now. Mind you, the game has not reached any sort of critical mass and requires additional players online while you’re playing to provide the proper effect. For example, racing is a multiplayer activity. We’ve implemented a guest play mode in which players can have access, except that chat is disabled and your progress/car changes/points are not saved.
Please feel free to check it out!