It's not over yet. The GDL union (which represents German train engineers) has promised not to initiate strikes through the holidays. However, German news agencies are reporting that there will be "massive" strikes after January 11 if DB fails to provide, by December 17, the sort of offer that the GDL wants. Such an offer would include not only wage and hours concessions but also a widening of GDL's authority to represent other DB employees as well (who are now represented by a competing union.)
Recent strikes (which union bosses now refer to as "Kinderkram" or "child's play") have involved serious interruptions of service over several days. This week's escalation of rhetoric should be taken seriously by anyone planning to travel in Germany after the holidays. I would either make alternative travel plans (long-distance bus companies are booming, thanks to this conflict) or postpone planning until the conflict is resolved. Some alternatives: