Markus, in answer to your question:

(1) Should we merge Relations with Attributes by providing a new datatype, and
by treating untyped attributes as relations by default (instead of rejecting
them as done now)? Why?/Why not?

Yes.  Having separate distinct relations and attributes doesn't add any significant capability to SMW, but it is confusing to new users.  It is better to be as simple as possible, while maintaining functionality.  (am i wrong?  what is added by having these things be separate?)

(2) If only one remains, should we rather use the syntax "::" or ":=" for
annotations? The syntax ":=" suggests a way of writing inverse relations in
queries via "=:", but maybe this is not obvious enough to be a good idea.
Which syntax looks more user-friendly in general?

I would suggest  '::'.  Again, it is simpler.

(3) Should we call the remaining semantic elements "Relations"
or "Attributes"?

I think either works.  But I like 'relations', because it emphasizes the interconnectedness of the data. 

(4) How would the type "wikipage" that is used for emulating relations be
called? "Article", "Page", "Wikipage", "Link", ...?
I think 'wikipage' is clear, but not elegant.  Another option is to have the type be "relation".  (In this case the semantic elements would need to be called 'attributes', and one type of attribute is a "relation".  It fuzzies the terminology of entity relationship modeling, but it could work).  "link" is also a good choice.

Nick

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Nick Grandy
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