Yet, in this context, let's consider HTML5's potential for the so-called "rich content" — that is, let's just consider how we could create animations and toons similar to what can be done with
Macromedia Adobe Flash.
Flash is currently ubiquitous. Not because people love having another plugin in their browser; those aware of a concept of plugin don't like having yet another plugin. Especially not the one that slows page loading; let's remember Java applets. User doesn't like browsers that crash; Flash Player can cause that to happen. User doesn't like slow speeds that Flash Player delivers.
However, apart from Smokescreen, which again plays with Flash, every single Flash-like animation was tediously coded by a geek programmer. JQuery may make stuff simpler, but it's not designer-material!
HTML5 animation needs proper authoring tools.
There is a market for HTML5 animation authoring tools.
Layers, tweens, reusable "symbols", grouped "symbols", vector elements, bitmap elements, at least basic early-Flash-style event handlers .. Give designers that, and they may jump on the Flash-less train.
In fact, even a geek like me will prefer using Flash, because doing HTML5 animation is tedious. Flash, despite being ruined compared to its early days, reigns as a creation tool.
I'm even willing to privately pay for an HTML5 animation tool. Not too much, but I'm willing. Someone out there to snatch my cash? (Apart from Adobe, I don't like them as a company.)
* I admire Flash artists — except those that create ads, I hate Flash ads passionately