I believe that every class which has an online aspect needs to have some private space for the class, independent of whether it has public space as well. Compass affords just such a private space. Moreover, I think it really bad design to "put everything into the discussion board" for example, by having lecture notes and syllabi as file attachements to discussion postings. Further, blogs, as distinct from discussion boards, don't enable threading. The linear approach in blogs is fine if the idea is straight narration. It is less good as a browsable interface. Finally, there are other tools in Compass - quiz and grade book are examples - that are separate from the discussion board and yet these tools are useful to use in conjunction with each other. Compass is great for that. So I am very pro using Illinois Compass for instruction and certainly want to promote that.
Compass may be useful for non-instructional purposes, but now things become a little harder for the designer, especially regarding user management. If one used a development site as collaboration, say for a workgroup in a lab, then the other members would have to be added to the site one at a time and the information requirement is knowing their netid. There is no way at present to add multiple users in one fell swoop, especially not with the section level access that we are giving, nor a way to do lookup of netid based on their name. (This latter functionality does exist at the course level.) The other issue is adding non-uiuc users. They must have accounts loaded into the global database and doing that is a manual thing for CITES staff. We will do it when we see the value in the teaching and learning. But it is a clunky solution.
It is also worth pointing out that even in the instructional setting, there may be an interest or need to have a public site that is open to accompany the closed site in Illinois Compass. If this is just for showing files, the Netfiles service can be used. But if this is to allow more interaction and participation by people off campus, then some other approach is needed. The Group or Blog may fill that need well.
Getting back to the non-instructional use, there is a big convenience issue to think through. If the group is small or with static population, straight email may be an effective solution. That happens all the time. But if the group is large or with a dynamic population there needs to be a more proactive way to manage the group and that group management capability should be distributed not centralized. The commercial environments do this better than our campus does it right now. There is a question of whether the campus will catch up. I hope so, but I'm skeptical.
The other point here is on bringing others into the conversation as lurkers, deliberately allowing them to lurk only, not to post. There likely are multiple possible ways to do this, but generating some xml feed of the site seems an integral part. Currently, those type of xml feeds are not generated by anything that CITES supports. So that is something to think about in addition.