It appears that there is quite a bit of interest around the recent LinkedIn® Subgroup announcement. As a webtool, it seems to provide an answer to many needs you have been asking for. Two key questions have been coming up and the answers are here:
1) How many subgroups can I join?
You may join up to 50 subgroups across all parent groups. This total does not count against your parent group total of 50.
2) How many subgroups can I create for my parent group?
Up to 20 subgroups can be created within a parent group, but any individual can only create up to 10 Subgroups across all groups. This limit does not count against your parent-group limit of 10.
If you have additional questons, leave them below as a comment and I will get you the answers as soon as they are available. The link to the original announcement and analyis of the impact is here.
is it possible to turn a sub-group into a seperate main group and if yes, how do I go about that?