I have asked the resident HTML WG RDF guru to reply to this.  However, 
basically you should think of the role attribute as an abstract enabler 
for binding accessibility to parts of a document.  The property 
attribute is more for defining explicit metadata about portions of a 
document (or the whole document).  I am confident that Mark will do a 
far better job of explaining this than I ever could.  Suffice to say 
that the resulting RDF tuple for the two expressions below is very 
different.

Sjoerd Visscher wrote:

> What is the difference between
>
> <span role="dc:creator">Sjoerd Visscher</span>
>
> and
>
> <span property="dc:creator">Sjoerd Visscher</span>
>

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Shane P. McCarron                          Phone: +1 763 786-8160 x120
Managing Director                            Fax: +1 763 786-8180
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