I'm a student at the University of Toronto Museum Studies Program, and
I was surprised when our museum education class concentrated on
informal education.  We were taught by two museum professionals from
Toronto.  It seems that a lot of information about informal ed. has to
be found outside of museums literature.  We spent a lot of time trying
to develop a model of the visitor's experience.  We couldn't agree and
couldn't find any models that suited everyone's conception of what
processes visitors go through within an exhibit.
 
So as a long winded answer, yes people are thinking about informal
education and museums, but the answers aren't clear.
 
Carol Martin