This talk describes a vision of processing-centric networks that unify In-Network computation and programmable communication. This convergence of computation and communication enables a high degree of flexibility in the design and operation of distributed applications that run „on top“ or „within“ these networks. We specifically consider some of these applications that must adhere to given performance requirements, e.g., on timing, with a main focus on Multimedia Systems. Major challenges to the design and operation of processing-centric networks lie in the coupling of the programmable control of networks with application and network models that are fed with real-time feedback data. The aim of such coupling is to provide flexibility in combination with provable performance guarantees.