I didn't down vote, so I can't answer to that. The parts I found useful from "everything else" I listed above. LocalStorage is the big one (IMO). You get acc

I didn't down vote, so I can't answer to that. The parts I found useful from "everything else" I listed above. LocalStorage is the big one (IMO). You get access to a built in, cross session data store natively. The canvas element has some interesting potential applications. I don't think it's quite "there" yet, as far as performance goes on most systems. The reasons for the markup changes are to help standardize things. If you don't feel the need to do that, you don't need to. You won't find a whole lot in html5 that will affect what you do from a design standpoint (unless you start throwing in some canvas elements). Your plug and play jQuery scripts might take advantage of some html5 elements without you knowing, but they've sufficiently abstracted those details away from you, so that you don't need to worry about them. Those elements won't break if you're using HTML4 markup instead.