The IncludeTotalCount method is used in the Telerik's QueryableDataServiceCollectionView class, but the method is obsolete. Use IncludeCount instead. 
Using the IncludeTotalCount leads to "IncludeTotalCount Method NotFound" error when the user project references Microsoft.OData.Client package with version higher than 7.8.3.

The QueryableDataServiceCollectionView uses the Microsoft.OData.Client.DataServiceCollection internally, but intialized it with its default TrackingMode which is AutoChangeTracking. Add an option to allow setting the TrackingMode via the QueryableDataServiceCollectionView object and transfer this value to the DataServiceCollection. You can do that in the constructor of the QueryableDataServiceCollectionView. 

Introduce support using RadDataServiceDataSource in a .NET Core application.

A new binary named Telerik.Windows.Controls.DataServices60.dll will be available as of Q3 2015. It is build for WPF 4.0 and 4.5 and is counts on Microsoft.OData.Client version 6.13.0.  Its nugget package can be found here: https://www.nuget.org/packages/Microsoft.OData.Client/6.13.0