I had the same empty feeling after my first "demo" (yes, a bouncing ball). I agree when you say "I think my biggest concern about these tools is that they simply become a swap-in replacement for Flash and that people start to use them purely from a visual perspective and not considering the structure and semantic meaning which underlies all HTML pages." I hope this doesn't get thought of as some WYSIWIG animator. The environment feels like flash to me, and it would be great if it had something like Dreamweaver's Code View or Split view so I can edit the JS and HTML files right there in the same IDE.