RDIL/Natural RDF revision

I just posted a revised version of RDIL at
http://www.mobileink.com/rdf/rdf.html.  This one is more complete, focused,
and organized.  It contains a two-page table with formal (symbolic)
representation of everything that looks like a definition in RDF Concepts
and RDF Schema.  I would welcome suggestions/feedback especially on two
points:   treatment of blank nodes in terms of scoped equality, and
treatment of "leaning" as graph normalization based on syntactic congruence.
 There are notes on this in the doc; briefly, one idea is that blank or
unlabeled or transiently labeled nodes can be handled by 1) treating the
"transient" labels as indexical names rather than existentially quantified
variables, and 2) scoping the equality relation rather than the names.   The
other idea is that syntactic congruence can be defined for graphs containing
blank nodes such that reduction eliminates all but the "most canonical"
representative of the congruence class.  I think it'll work but haven't
worked out the details, so if anybody else is interested playing please drop
me a line.

Cheers,

Gregg