text: I've updated sidewalk to None as shared use path now maps the sidewalk on the left. Added a shared use link to the highway at the point of the dropped kerb in mapillary image above (and on my cyclecam). It does appear as if highway=crossing crossing=unmarked is valid for situations where there is no traffic lights or markings. Also sloped_kerb=no to indicate not suitable for wheelchairs. http://wiki.openstreetmap.org/wiki/Key:crossing
  New to me!