When you use IBM SmartCloud for Social Business Engage (SCSB) you get a contacts feature. It will list all your network contacts, but also is able to list arbitrary contacts, serving as your address book. Latest since the arrival of mobile devices however the saying goes: "only a synced contact is a good contact".
Well hidden in the SCSB help are the instructions how to sync with the Notes addressbook. Expecting users to edit ini files and use an Eclipse update site is (I nearly said silly) not in line with todays install expectations. It can be simpler: Drag this link into your "My Widgets" sidebar and the rest is automatic. Enjoy!
As usual YMMV.
Update: SCSB support