1. GrufSpaces don't seem to add much values since all functions are already
   implemented using GRUF and "sharing" in Plone 2.x. Am I missing something?

   You miss the workflow, which had to be changed so that all groupmembers
   can share the documents, meaning they can edit each others documents.

   This includes protecting the documents inside a GrufSpace from being
   visible to the outside (in case of a closed GrufSpace), and then offering 
   the possibility to open the GrufSpace and suddenly making
   all documents publicly visible including catalog searches.

   We also offer the possibility to add services or tools to a GrufSpace
   automatically. There is a script which is called when you create a
   new GrufSpace, and I will enhance it today with further examples.

2. What is the purpose of GRUFSpaces since they add more complexity and don't 
provide *new* functionality except portlets.

   Remember that GrufSpaces is currently at version 0.1.

   The purpose of a Group Space is to support the work of its members.
   Different groups have different needs, but a discussion group is a
   good example of a common need.

3. The use cases mention that members of workspaces can "invite" other members
   but I didn't find that functionality.

   Currently this is not implemented. A special tab is going to be added soon,
   and right  now invitation is done through the "sharing" tab by assigning
   a member the role GroupMember, which is unfortunately not including notification.

4. Which part of Plone or GrufSpaces would be responsible for deciding
   whether I should get a 'contents' tab inside a GroupSpace with Plone2?
   It doesn't always seem to be consistent and I find I often have to
   manually add folder_contents to the URL.

   That is decided in the action inside GroupSpace.py:

    'id'            : 'folderlisting',
    'name'          : 'Contents',
    'action'        : 'string:${folder_url}/GroupSpace_contents',
    'permissions'   : (CMFCorePermissions.ModifyPortalContent,),
   ##    'category'      : 'folder',

   You need to have the ModifyPortalContent permission to get the
   GroupSpace_contents view, which is equivalent to the folder_contents
   view.

5. I don't want GroupMembers of a GroupSpacee to be able to delete documents
   that they don't own. The solution is to change the workflow and to give only
   the Owner the right to "Delete Object". It works fine in Plone Folders, but as
   soon as you do it in GroupSpaces, it works no more.

   Solution: Make GroupSpace inherit BasePloneFolder instead of SkinnedFolder, so
   that the method manage_delObjects from BasePloneFolder gets called and gets a
   chance to execute the check:

   mt.checkPermission(Permissions.delete_objects, item)

   This will be corrected soon in GroupSpaces 0.2

6. Why can't members add PloneArticles in my GrufSpace?

   You could give the permission "Add PloneArticle" at root level.
