I think there should be a bigger emphasis on the "Canvas" function of HTML5, which is basically all that seems to be used in the demos. And, form what I've seen of Canvas, a sophisticated tool will be absolutely required, unless only math majors design with it!
I can't really say I know much more about HTML5 than that negative comment!
There are new coding/page divisions that are much more semantically helpful, but much of the rest of the system is still in the committee input stage. CSS3, OTOH, is much better supported, right now and IE9 will come as close as it ever has in compatibility when it is released.
While any html/css standard will be extremely valuable, the entrenched, already published material made with Flash is sure to be around and widely used for quite some time, iOS/Webkit barriers or not. It's not dissimilar to the Windows vs. OS X battle.