Flash, hell no!
Check out the SVG standard at w3c. (scalable vector graphics) thou rocketh. Its described via XML so is easily created/edited by any programming language or text editor, its scriptable/interactive, and as its by w3c its functionally consistent with existing css and javascript techniques making it very accessible to existing html/js/css scripters. It can be compressed by gzip svgz so doesnt take up much bandwidth. Lets hope its adopted as the standard in future.