Some of ideas here seems to be touching on Relational Aesthetics, by Nicholas Bourriaud. It might be good to interrogate the notion of interacting with a 'public' (who are they?) and creating relations as art from other angles. Clare Bishop's unpicking of his ideas and the artists used to exemplify them is very thought-provoking, and she also names some creators of rather more disturbing and tricky relations... she asks what kind of negative relations might be created in relational art, whether existing relations be simply affirmed, or curious types of non-relation be created?
It was on the reading list for one of Gavin's performance classes, so quite a few may have looked at it already:
'Antagonism and Relational Aesthetics', October, no. 110, Autumn 2004.
As an aside... maybe we can create our own -ism?