xHTML encourages well written, consistently formatted, code which is probably its most important feature. Many of the HTML5 features you mentioned I don't see

xHTML encourages well written, consistently formatted, code which is probably its most important feature. Many of the HTML5 features you mentioned I don't see as being features that belong within a document structure language. Geolocation and Crossdomain XMLHTTPRequest are browser issues they have nothing to do with a document and don't belong in a spec for a document definition. Native sound/video and offline support, of course, I agree with. But, if your application doesn't have the need for either of these features - what does HTML5 offer?