Since the publication of HTML 4.01, HTML standard was not changed. Many developers declared HTML dead and switched to XHTML. I am also not an exception, because I switched from HTML to XHTML Transitional, then to Strict and later completely to XHTML 1.1. Mostly I develop web pages based on TYPO3 and use many plug-ins. I have a lot of work in the adaptation of templates so that they generate a proper code. The reason is, different developers of the plugins are using different technoligy.
Today, I learned via Golem.de that Mozilla integraded into Firefox 3.1 a video-tag. Moreover, according to Golem, Opera and Safari made it too. This means that you can soon use video-tag instead of Flash or Silverlight. It also means that HTML is not dead, because video-tag ist a part of the HTML 5.0 specification.
It’s just so that when you are the developer, you have to lern every day something new. If you stop for some time, to lern new technologies, then you have bad cards, if you would like to stay in business for a long time. But why must it be so complicated? Why should I use parallel HTML and XHTML? Would it not make sense, to develop an once technology constantly, instead to develop multiple specifications? I could understand the situation if there was no organization which control the developing of standards. But this organisation exists! I would prefer to continue using XTML, instead of HTML 5, because there will be a chaos, between developers, who works on the same project, e.g. TYPO3.