I'm assuming that this is about your earlier post that ended up in LW's technology community. Microblog posts like that seem to be more intended for whoever is following you as a user. If MBIN insists that you also have to choose a 'sub' then I think it'd be best to put it in whatever it considers a dumping ground (ideally something that doesn't federate out), so the 'random' magazine sounds about right to me.