We have recently released 0.9 version of the Azure Active Directory Graph Service. The update includes some key improvements but it also comes with some significant breaking changes. We have just updated the .Net MVC Sample to work with the 0.9 version of the Service. As part of the sample, there is a thin helper library which includes the Service Reference for 0.9 version and includes some helper methods for setting up the required headers, query parameters etc.
As you can see, there are some significant changes in 0.9 version of the Service. If you hit any issues in upgrading your application to use 0.9 version, do let us know and we will be happy to help.