Sandro Hawke has announced the early release of graph comparison
functionality in blindfold,
his developing semantic web toolkit.
Hawke writes:
The problem I'm addressing here is: Do two RDF/XML files (or other RDF
graph encodings) convey the same information? If the information is
different, what are the differences? What would have have to remove
from each file to make them say the same thing?
For more information, read the announcement in full.