Help with HTML5 and RDFa please

Hello. I hope that this is the right mailing list to which to post this question.

I'm trying to establish the correct syntax for using RDFa with HTML5, particularly with respect to what goes in the head of the document.  My blog, http://ricroberts.com, currently generates HTML+RDFa but I'd like to get it to work with HTML5.  

I've read this document: http://dev.w3.org/html5/rdfa/rdfa-module.html, but I'm still not really clear about how to go about converting things to work with HTML5.

Here's an example of a working page in HTML+RDFa format:
http://ricroberts.s3.amazonaws.com/ricrobertshtml4.html

....which validates fine on the W3C validator:
http://validator.w3.org/check?uri=http%3A%2F%2Fricroberts.s3.amazonaws.com%2Fricrobertshtml4.html&charset=%28detect+automatically%29&doctype=Inline&group=0&user-agent=W3C_Validator%2F1.767

Here's my latest attempt to get it working with HTML5:
http://ricroberts.s3.amazonaws.com/ricrobertshtml5.html

....but as you can see, it the W3C validator doesn't like it (it's complaining about certain attributes, such as namespaces, 'about' and 'property' etc not being allowed where I'm using them).
http://validator.w3.org/check?uri=http%3A%2F%2Fricroberts.s3.amazonaws.com%2Fricrobertshtml5.html&charset=%28detect+automatically%29&doctype=Inline&group=0

Note that the RDFa distiller service seems to happily be able to parse the RDFa in both versions:

HTML+RDFa: 
http://www.w3.org/2007/08/pyRdfa/extract?uri=http%3A%2F%2Fricroberts.s3.amazonaws.com%2Fricrobertshtml4.html&format=pretty-xml&warnings=false&parser=lax&space-preserve=true

HTML5: 
http://www.w3.org/2007/08/pyRdfa/extract?uri=http%3A%2F%2Fricroberts.s3.amazonaws.com%2Fricrobertshtml5.html&format=pretty-xml&warnings=false&parser=lax&space-preserve=true

Thanks in advance for any tips.
Regards,
Ric Roberts.