Just read this news from Tim Anderson’s blog,
it appear that the W3C working draft has a statement about the use of proprietary UI languages.
As an open, vender-neutral language, HTML provides for a solution to the same problems without the risk of vendor lock-in.
For sophisticated cross-platform applications, there already exist several proprietary solutions (such as Mozilla’s XUL, Adobe’s Flash, or Microsoft’s Silverlight). These solutions are evolving faster than any standards process could follow, and the requirements are evolving even faster. These systems are also significantly more complicated to specify, and are orders of magnitude more difficult to achieve interoperability with, than the solutions described in this document. Platform-specific solutions for such sophisticated applications (for example the MacOS X Core APIs) are even further ahead.
Even if HTML5 seems to be heading in the right direction:
- New Structure
- Block semantic elements
- Inline semantic elements
- Embedded media
The only point where I see an overlap with Flash or Silverlight technologies is for ‘Embedded Media’ and ‘Interactivity’.
However those are just a minor part of what is feasible with Flash…
So no, for me HTML5 is not going to make me stop using Flash & Flex, for Silverlight it’s another question as I didn’t even started using it…
For the semantic part, well I’m looking forward to use those new HTML5 elements, but seems that I’ll have to wait a long time 🙁