RDFa Primer -- some comments

Greetings, I have been looking at the latest, in progress, draft at 
http://www.w3.org/2006/07/SWD/RDFa/primer/20080422/ and have a few 
comments. 

I think this version is much better that the previous versions. 

2.1 Licensing your Work
http://www.w3.org/2006/07/SWD/RDFa/primer/20080422/#IDA1FX3C

includes the following example 
...
All content on this site is licensed under a
<a rel="license" href="http://creativecommons.org/licenses/by/3.0/">
    Creative Commons License
</a>.

but the image shows something different: 
  distributed under 
  a Creative Commons License
 
 
2.3 Multiple Items per Page
http://www.w3.org/2006/07/SWD/RDFa/primer/20080422/#IDAAZX3C

in the previous section you introduced "@property, a new HTML attribute 
introduced by RDFa"

but here you say "RDFa provides @about, a new attribute", is this also a 
new HTML attribute? Why describe differently if you want the user to 
understand that they have something in common? Same applies to later 
attributes.

what does the example -- about="/posts/trouble_with_bob" -- actually refer 
to? Looks like a relative reference, but relative to what? Same for -- 
about="/posts/jos_barbecue" -- 

The figure after the example clears it up, I think.

-- about="http://example.com/bob/photos/sunset.jpg" -- seems clear

Why not start with the absolute example and then illustrate a relative 
one?

3.1 Contact Information
http://www.w3.org/2006/07/SWD/RDFa/primer/20080422/#IDAJ0X3C

the dreaded blank node! While this section improves on the last version of 
this document I still think a lot a care is needed to introduce the 
concept and its usage. 

You state: . . . This node has no URL to identify it, so it is called a 
blank node.

Nowhere in the earlier sections is there a definition of what constitutes 
a node which makes the introduction of a new "kind" of node, a "blank 
node", tricky. The diagram includes a node labelled _:blanknode1, which is 
presumably meant to represent the "blank node". Why such a strangely 
formatted label? Can the connection be made clearer. 

One example includes 
<div class="social-network" about="#me" rel="foaf:knows">

where is there something that establishes the connection between #me and 
http://example.com/alice#me.


Regards, Roland
FBCS, CITP





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