Frank,
This table looks interesting. I think figuring out which parent object to check for permissions is very helpful. I just talked to some people at the meeting in Madrid who used the same strategy. The biz_object_id, which is the topmost container would be useful. In OpenACS this would probably be a content folder, a package instance, or a subsite in most cases.
The search observer queue is to keep search indexing running in a seperate thread to not slow down object creation. It works fine and the abstraction is not a problem. I also think the new callback based procedures for datasource make it more flexible and much easier to define a new object type for searchability.
We had a meeting on search in Madrid, I will be posting the notes in the next day or two.
