In general, wpViewObject should be used instead of this method because wpViewObject takes into consideration the setting in the Object Open Behavior field on the Window page of the Settings notebook for the object. If a view of the object is already open, wpViewObject will, depending on the setting of the Object Open Behavior field, either display the existing window for the object or create a new object.
In contrast, wpOpen always opens a new view of the object. Under certain circumstances this might be called for; however, under most circumstances, wpViewObject should be called instead.