What can be done through XFrames, as compared to iframe in html?
Is there any new feature other than making it easier to bookmark in XFrame as compared to IFrame?
Xframe has never been implemented in any version of XHTML. It was proposed in a separate working draft by the XHTML2 working group while working on XHTML 2.0. The XHTML 2.0 working group itself was closed in 2010. The next version of XHTML is XHTML5, and is part of the spec being developed by the HTML5 working group. Xframes is not part of this spec.
HTML5 and XHTML5 support