Pros
Almost nothing I can think of. I worked at several large companies in 5 countries and Tamedia was by far the worst experience. Perhaps the only positive are decent salaries.
Cons
Very old-fashioned, the office in Zurich is very basic and designed around saving rather than offering anything to the employee. Meals in the canteen are quite cheap by very heavy and traditional and there's hardly any selection. Although it advertises itself as a company hiring internationally, it's very German language-centric, a lot of communication is available only in German.