I recently found out about the online paint application, Sketchpad (http://mugtug.com/sketchpad/).  Everyone seems to think only HTML5 is responsible for this as if learning the "HTML5" markup language alone will allow them to create this wonderful app and say goodbye to Flash.  Yes, this technology will beat Flash, but you'll probably need to know lots of JavaScript before you can start making such dynamic applications.  Take a peek at the Sketchpad source and you'll see that it seems 90% of the script is JavaScript.  If designers thought coding in Flash ActionScript was hard, well things are about to get a little harder!  I could be wrong, but there are probably more syntax keywords and APIs to learn in JavaScript than ActionScript.  There's JQuery and Apple's "Canvas Element" which is the API in HTML5 that is used in Sketchpad.  You heard me right, APPLE, aka Steve Jobs, aka the pretty geeks' computer company has a key component that's part of the HTML5 specification.  Well, I can't wait to learn more about HTML5, but it seems like I have to wait if I want a book.  Amazon.com currently reports that HTML5 books are only available for Pre-Order! (BTW, IE lovers, this sample app doesn't work in IE8!)