I don't yet know enough about HTML 5 to mention any problems.
But specifically, I really do like the inclusion of Math ML.

  The posting trouble I mentioned is generic.
Submitted posts are usually not filtered for any HTML code.
Then, when presented as part of a forum page, the browser
just runs any code it finds.

I've become a proponent for the Separation of Code and Data.
   code, code, code... ; ... data, data, data
But forum sites and e-mail services just don't get it.
I was astounded when I first saw MS Exchange allowing embedded HTML.

  In general, all HTML tags are a poor syntax and a pain to use.
Un-matched pairs and missing of end-tags, give rise to defaults 
having unpredictable results.

  ¿Entendemos?

  (-:  Chas.M.  :-)

> Subject: Re: text-level semantics and the blind?
> From: alex@crackpot.org
> Date: Fri, 28 Jan 2011 08:07:44 -0600
> To: plug-discuss@lists.plug.phoenix.az.us
> 
> 
> On Jan 27, 2011, at 9:41 PM, Technomage Hawke wrote:
> 
> > Chas,
> > now you begin to see some of the problems I experience on some sites right now. html5 is going to make things at least 1 order or magnitude worse.
> 
> Are there particular aspects of HTML 5 which are problematic?
> 
> alex
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