I guess I'm not sure what you mean by compliant. Clearly OOGL
is compliant to OOGL, and Inventor is compliant to Inventor, and
there is no interoperability between the two. Since both are
equally VRML, both are compliant?
There is a habit on the mailing list to fail to distinguish,
and use the letters "vrml" rather lazily. But having actively
participated in the group for 6-9 months now, I am not aware
of any compliance or conformance standards or test suites, or
of any branding effort for either OOGL or Inventor. Basically,
the SGI folks said, "yea, verily, this is our file format, yea
verily", and likewise for UMN. Likewise, any third major file
format to come along would also be VRML, without any requirement
for compatibility with any of the other two.
Given that there are lots of potential 3D file formats that
could be fairly easily integrated with web browsers, a lot
of the actual chest beating of "we've got the real vrml" is
marketing hoopla.
--linas