In this article, Steve Hunton explains that, even if people expect that the shift to Agile practices includes a wholesale shift of roles,, the ScrumMaster does not play the part of the traditional project manager. He thinks that the project manager role is more filled by the product owner. The project manager is a decision maker accountable to the business for accomplishing the project objectives. The ScrumMaster is a coach and facilitator that sits between the project and the customer. He isn’t responsible for the project or managing the development team. If you have questions about the product, then you should ask it to the product owner. He concludes that if the ScrumMaster is making decisions about a product, then Scrum has not been properly implemented and there’s going to be confusion and conflict about who does and owns what.
