X/HTML5 vs XHTML2

So, which one should I pick for a new imageboard script currently in the making?

xhtml is nice because you can run it straight through an xml parser. but html is equally easy to parse with the right tools. xhtml has been integrated and used quite nicely on Blogger.com's templates. that kind of thing is the only difference of which i know that is a real big difference between xhtml and html.