XHTML -- Still Relevant?

[spufi]

Meanwhile, using the XHTML doctype, my page validates just fine:

The validation of XHTML 1.0

BTW, here's the page in question: http://mrinitialman.com/Books/HTML/C...lue_Types.html It's part of my HTML book.

I'm shocked a web page written in XHTML validates as such and yet doesn't validate as HTML 5. Shocked I tell you.