Joost joins the list of real world applications that are eschewing blank nodes in their RDF. At Talis we're doing the same - our RDF versioning protocol doesn't support bnodes either and we actually replace them with URIs in many places. Over the past year I've spoken with several companies making practical, commercial use of RDF and none of them are using bnodes. In fact they are actively avoiding them. Two of these companies claim to have stores in the multi-GigaTriple range.
So far I haven't found a use case for bnodes that can't be catered for by URIs - can anyone prove me wrong?