A presumably candid post from the IEBlog reveals that Internet Explorer 7 will not support the MIME type "application/xml+xhtml". The reason given is that implementing this in IE7 would be done using the HTML parser and could end up being a hack. Chris Wilson hints that a future version of IE will support the MIME type and it will be implemented properly. As long as the release schedule for Internet Explorer is under a year per version, I'm happy with that.
They do reveal that IE7 will properly skip the xml prolog and handle XHTML in strict mode (instead of quirks mode). He also states that it is relatively easy to configure a web server to serve text/html instead of application/xml+xhtml when the user agent does not support application/xml+xhtml. This is a step forward, but it looks like XHTML will still go nowhere until IE8.
Has it been 100% confirmed that it wont support it?
Do you want to know something utterly ridiculous? The Microsoft website is designed using XHTML. I don’t quite see why they won’t support it in their browser yet they will use it for their website. Microsoft will very quickly lose all of their market share in the browser market, so I don’t quite know why they are wasting millions developing a new version.
Microsoft is holding back the web. IE is like a deadbeat parent that gives their kid a Christmas gift in February.