Software that uses Artificial Intelligence technology like Machine Learning is becoming ubiquitous with even more applications ahead. Yet, the very nature of these systems has made it very hard to understand how they operate, creating a demand for explanations. While many approaches have been and are being developed, it remains unclear how strong this demand is for different domains, application types, and user groups. To assess this, we introduce a novel survey scale to quantify the demand for explainability. We also apply this scale to an exemplary set of applications, novel and traditional, in surveys with 212 participants, showing that interest in explainability is high in general for intelligent systems but also traditional software. While this validates the heightened interest in explainability, it also reveals further questions, e.g. where we can find synergies or how intelligent systems require different explanations compare to traditional but equally complex software.