I learned how to play this song very early on too. I understand you linked to the online keyboard on this site, but it would be really helpful if you included a keyboard on this flash tutorial as well. The fingers being numbered trick looked very effective, you would make a good music teacher in that department. The overall flash looked bland as there was a drawing and a blank background, it could use some more diagrams or examples to keep the viewer interested.
I was never a big keyboard fan, but I know how to play a few songs. I was always more of a saxophone player, but even a novice pianist like me learned information from the tutorial, so I think you have achieved your goal. Keep working at telling people vividly how to play and I'm sure your flashes will gain popularity. Keep up the good work!