What's the future of the web? XHTML 2, HTML 5, or something else?

Question

I'm confused by the discussion and advancement both of a new version of HTML and a new version of XHTML. Are they competitors? If so, what is likeliest to be the adopted future of the web? If not, what is the differing non-competing purpose for each?

Are we due to have a BluRay/HDVD battle here? Is there ultimately any clear decision? I fear a future where browsers pick and choose among the easiest and/or flashiest features of each to implement, leaving web developers trying to sort out the lowest common denominator for any new web app.

Answer 1

HTML 5 is meant for web applications whereas XHTML2 is meant for documents. From the HTML 5 working draft:

XHTML2 defines a new HTML vocabulary with better features for hyperlinks, multimedia content, annotating document edits, rich metadata, declarative interactive forms, and describing the semantics of human literary works such as poems and scientific papers.

However, it lacks elements to express the semantics of many of the non-document types of content often seen on the Web. For instance, forum sites, auction sites, search engines, online shops, and the like, do not fit the document metaphor well, and are not covered by XHTML2.

[HTML5] aims to extend HTML so that it is also suitable in these contexts.

XHTML2 and [HTML5] use different namespaces and therefore can both be implemented in the same XML processor.

Answer 2

XHTML2 and HTML5 are competing standards, they both purport to be the next iteration of HTML.

It is pretty clear that HTML5 is going to win, since it has support by the browser vendors.