I'm sure you know that Scribd is switching from Flash to HTML5 and Apple is rumored to be doing the same. Well, the Scribd announcement got my attention. It's a sign that HTML5 has gone mainstream, and I probably need to learn about it.
I came across a new site yesterday that has HTML5 demos. (I'd bookmark it if I were you.) If you visit the site you'll see a bunch of things that can be done with HTML5 as well as what particular features your browser supports right now. Check it out.
And in case you're interested: