Deirdre,
Thank you so much for your last couple of posts... they have been really very helpful.
The subgroups (and sub-subgroups) will be a killer function for the medical school here in Heidelberg (it was one of the things that made the decision to go with dotLRN easy). In the recently implemented reformed clinical curriculum, which focuses on problem based learning in small groups, teamwork becomes essential (just like in the hospital later). At the same time large 200 person lectures have been broken down into groups of 30-40 which cover the same material in blocks. The fact that a large amount of control and flexibility can be delegated to the group admins is excellent and makes such scenarios simple. Subgroups allows dotLRN to mirror reality more efficiently, which I am sure will be a factor in its success.
I find it so exiting to see the dotLRN born in a business school mapping so well to the structures found in a medical school! I really look forward to the implementation here in Heidelberg... this will be a process that I will try to document for the community as it takes place.