Some, and yes.
See http://home.iclweb.com/icl2/mhkay/GedML.html
My approach with GedML was to define an XML encoding of the existing GEDCOM
data model. this gives you two-way convertibility, but it means all the
limitations of the GEDCOM data model are still there, so all you really get
is easier parsing. Others have experimented with extending the data model,
but then you start to lose out on interoperability. As always with standards
it's hard work to move something forward when there is a large existing user
base.
Mike Kay