@jgoerzen the wikipedia article tells us the librarything is partly owned by amazon; i don't know if that is true.
when i think about possible sellouts, that means anything privately owned can be bought and sold… unlike structures like archive.org (behind openlibrary) or bookwyrm. again, i don't know for real.
i have a bookwyrm profile, but you're right, it's not nearly (or at all) fitting the bill of cataloguing :-(