Blank nodes

The RDF documentation says:

A blank node is a node that is not a URI reference or a literal. In the RDF abstract syntax, a blank node is just a unique node that can be used in one or more RDF statements, but has no intrinsic name.

Tracker treats blank nodes as an URI generator instead. The string referencing a blank node (e.g. as returned by cursors) permanently identifies that blank node and can be used as an URI reference in future queries.