Airberlin as an airline will close the shop this week. The last flight should operate this coming Friday. NIKI, the Austrian arm, will continue fly.
There are now several official matches from number of Oneworld airlines that are trying to get Topbonus elite members to match their status. Topbonus as a program may continue to exist as Etihad owns 70% of it. The most obvious choice would be for Etihad simply to merge it with their Guest.