May be actual users can fill in the gap:
I see the following changes:
New XML variables in web.config:
UseDNNRoleASFileNamePrefix="true"
UseDNNDefaultWidth="false"
- Email link (mailto:) bug (when you have multiple email links, they are altered to become the same one)
- image root is now pointing to /portals/0 instead of /portals/0/Member
- File security based on role (Adding 'Member_' prefix)