XHTML: What is it Good For?

With IE8 nearly upon us, discussion on the future of web standards has once again been triggered. Again lacking in IE8 is support for XHTML, ensuring that IE is the only browser that doesn't support it.

The goal of XHTML is to allow XML technologies to be used with HTML. XHTML has been a standard now for about five years, and IE is still (single handedly?) preventing websites from adopting it. Instead websites are forced to use server side solutions that require more bandwidth and processing, while making it harder for non-traditional agents to participate.

Within recent discussions on XHTML many people seem to fail to understand the potential benefit XHTML has over HTML. An interesting example I came across was combining XSLT and XHTML together.

I have written about XSLT before
http://jamesrdf.blogspot.com/2008/12/mvc-with-xslt.html

This example is from 2002 (around the time XSLT and XHTML were standardized) and can be found in more detail here:
http://www.webreference.com/xml/resources/books/practicalxml/chapter5/

As most of us know, XHTML is also an XML file and as such can be used as the input or output of XSLT. What many do not realize (and what is not covered in the above link) is that XHTML can also be used as the stylesheet. XSLT supports a simplified syntax that allows XSLT tags to be embedded inside an XHTML template file, making the template look a lot more like other server-side templating engines.
http://www.w3.org/TR/xslt#result-element-stylesheet

This allows you to use XHTML for the template and the content, and it works in all browsers, except *one* of them. Actually, you can get this to work in IE (even as early as IE5), but you have to use the XML rendering mode.

The XML rendering mode requires that the pages return application/xml and no doctypes present. Unfortunately by using the XML rendering mode, no HTML-specific features are available: no cookies, no document.write and script tags are parsed differently.

TV Series.com is rendered in XML mode, for example: http://www.tvseries.com/

If IE would get around to implementing XHTML, I think a lot more websites could safely switch to serving static files and the Web would start to become a lot easier to work with. But that probably wouldn't be good for Silverlight.