I had a glance at the interesting discussion thread about sorting here, but I am still left wondering how manual sort order is stored as metadata. Is it something that could somehow be included in properties, and hence as a column in other views? As far as I can tell, it is currently stored as metadata but not visible to the user, except in its visible result (e.g., the sort order). Am I making any sense? (If not, I can explain further what I mean.)
(Note: After writing this post I came across what may be a bug relating to manual sort order. See here.)
Update: I have now discovered this thread and this Mantis entry.
Thanks,
Lucas