Well of course, if we do not finish, we will release what we HAVE. That said, we are making a demo for you guys to try, but we're not going to release every tech demo we make. If you want to try it, you're welcome to come onto the forum and learn how, or talk to us on the IRC and we'll help you, but if we released this in its current state, or tried to "complete" this, it would take away time from the real project.
Edit: A user on the forum is trying to complete it on his own time, so when/if he finishes it, I will release it. Another reason is, a user on our forum IS working on a separate hack called "Super Mario Sunshine Wii" which will be similar to what you saw in that video.