I think we will find it benificial to discuss some scenerios of
annotation usage to make sure that we are all on the same wave-length.

I break scenerios into two broad catagories -- authoring and usage.
Authoring scenerios provide scenerios for how annotations are
authored and usage scenerios provide scenerios of how an end-user
might use annotations.

Below is an end-user scenerio:

What sort of interactions does an end-user have with annotation sets?

1) Somehow, the end-user needs to find interesting annotation sets.
   Some possiblities include:

   A) They might get the name of one E-mailed to them by a friend.

   B) They might find the reference to one on a Web page they are browsing.

   C) They might go to a Web service that maintains lists of active
      annotation sets.

   D) They might subscribe to an annotation set (I'll call it a meta
      annotation set) that inserts annotations on every page that
      is annotated.

   Service C and D might be related.

2) Upon identifying an interesting annotation set, the user needs to
   be able to add it to their browser somehow.  Some possibilities include:

   A) Edit a file that contains one line for each desired annotation set.
      (I'm not a big fan of this solution. :-)

   B) The user visits the home page for an annotation set and through
      some sequence of mouse gestures clicks on a button that says
      `Add current page to your annotation set list'.

3) What sorts of operations does the end-user do to their annotation
   set list?

   A) The user needs a way to reorder the annotation sets in their
      annotation set list.  For non-embedded annotations, this would
      change the display order when two or more annotations sets
      contain annotations for the same target document.

   B) The user may want to temporarily enable or disable an annotation

   C) Deleting an annotation set from the list is a desirable operation.

   D) It is possible to envision performing operations between annotation
      sets.  For example, only show me an annotation for set A if there
      is a corresponding annotation in set B.  This would allow the end
      user to subscribe to both a PRO-topic annotation set and CON-topic
      annotation set, and see both annotations when they reference the
      same target document.

   E) How does the end-user specify that they are interested in seeing
      annotations recommended by the target document author (so called
      1st party annotations.)

4) Are there any end-user operations that are done on specific
   annotation sets?

   A) A user may want to visit each annotation in an annotation set.

   B) A user may want to visit each new and changed annotations in
      an annotation set.

I'll try to type in some authoring scenerios tomorrow.