Architectural Alternatives on how to "publish" (create an immutable, publicly readable version/copy) of an entity:
create a copy as a new entity
downside: entity appears twice in search results
create a copy into something that's not an Entity (e.g. into HTML)
change the owner, give read-only ACL (don't move to new folder)
downside: entity appears twice in search results
downside: cascade delete counteracts immutability (but might work around by walking tree upon move or delete request and stopping if published entity is descendent. This has other repercussions, e.g. locking down an entire tree)
change the entity's owner, move to new folder ("Published"), give RO ACL
downside: entity appears twice in search results
downside: lose context (but maybe can recreate using links or Activities)
create a new version, remove ability to modify old versions; previous version becomes publication
downside: only annotations and data file are currently versioned