(Meh. Don't particularly care for that one just yet. I don't really see what the problem is with Flash, other than it won't work on iPhone and other mobile devices but that's an issue of Flash's interactivity colliding with touch-screens.)
Anyhoo, Neil McAllister has an in-depth essay about HTML 5 and what we can expect from it at the InfoWorld site. Well worth reading even if you're just a casual tinkerer with HTML.