Okay, I had this problem as well. I solved it by turning on the debugging of Service Contract, unbinding all Fts* Service Contracts, and then install them again. *restart*.
If you don't have the proc mentioned above, FTS won't be able to index your content, as it does not know how to get the content out of ETP (datasource...).
As for the search_observer_queue. Good question, but I assume you are fine with creating a proc to index the content_item instead. But don't ask me for details ...
OTOH, I would first try out, if you can get a new item registered and debug how this happens. Once you get newly published items to show up on the search, try the insert again, as you might have to select revision_id instead of item_id, but I might be utterly mistaken (shooting out of my gut here).
