Add a method that allows you to start a cell animation when its content (the bound property of the underlying data item) changes. 

Currently, the FilteringControl orders its filters in a StackPanel with a vertical orientation, which means that the distinct values list is placed above the field filters. Add an option to allow changing the position of the distinct values to the left or right (consider also bottom).

This is useful if you want a more compact view. Also, the feature will resolve several corner cases where the screen doesn't have enough vertical space for the Popup and its contents get clipped.

Currently, if you have a SelectedItem assigned and you try to set the SelectedItem property to an object that is not presented in the current data view, the control keeps the previously selected item. For example, if you have items 1, 2 and 3 where 1 is selected, and you try to select 4, nothing will happen.

By "current data view" I mean the items that are left in the GridView's Items collection. Those exclude the items that don't match the filtering or search criteria if such is applied.

Add a property that allows you to change this behavior. In case the assigned item cannot be selected, the selection should be cleared. 

Currently, when you click on a cell in the row, the cell or the row get selected (based on the SelectionUnit). Also, the current cell is changed, which can be indicated by the border added to the clicked cell.

Add a mechanism to disable this functionality. For example, a new property on the cell (ex: CanUserSelect) that prevents selection and currency change on cell click. 

Allow customizing the FieldFilterControl shown under the column header when the FilteringMode is set to FilterRow. Currently, you can customize this only via an implicit style or by looking into the gridview's visual tree in code. It would be useful if you can define a style per column.

Currently, the splitter is drawn with few pixels and a background color based on the current Telerik theme. Add an API like a Style or another type of property that allows you to change the default color and width of the splitter.

We can implement drag-scroll behavior when dragging column across the headers section of the columns.

Currently, RadGridView's data engine relies on TypeDescriptor.GetProperties, when resolving the set of properties accessible through a certain type. Apparently, this API hides the properteis from the interface, as they are not accessible throught the concrete type.

When the ItemsSource of the RadGridView is set to an implementation of ICollectionView, the Groups property is not utilized, since the groups are generated internally by the RadGridView. We can consider introducing support the Groups property to allow for grouping customizations.

Add support for different merged cells orientation - MergedCellsOrientation.Mixed could be added.

The user wants an API with which he can set a formula. For example, the string "=A1+B1" will be translated in Excel like a formula.