Wasn't SAX designed on an open list?  Hasn't the schema been designed 
on an open list? Most of the work XLink is based on is public.  All of
the information 
you need to create open hypermedia linking is in the HyTime documents.  
All of the XML syntax data is open.  Take the XLink draft, clean it up, 
put new names on it, then publish it and implement it.  If you can 
do that faster, you may get a better result.  If you decide to 
adapt XLink when it is released, you probably won't too far off 
the mark.
If a closed society doesn't provide results, open one.  So far, VRML 
is doing pretty well with that approach.
len