While with traditional QoS-based charging the pricing structure mainly reflects the delivered QoS in order to regulate the demand, the role of service prices in a Quality of Experience (QoE) context is more complex. Amongst others, the charged price may in addition have a direct impact on the user's quality perception. In this paper, we analyze the structure of the resulting fixpoint problem and discuss the corresponding equilibrium. Based on recent user trials, additional insight into the characteristics of the related feedback loops is provided, before we conclude with outlining some consequences for future QoE-based charging mechanisms.