Introducing T23751 specific widgets have been implemented to establish a new selection concept. We need to find out if the QmitkDataSelectionWidget (which exists two times, inside the MultilabelSegmentation-plugin and the Segmentation-plugin) is needed anymore.
The QmitkDataSelectionWidget uses the new selection concept widget SingleNodeSelectionWidget. So it is not redundant per se.
But it is right that it makes no sense to dublicate the widget in the plugins. It should be in MitkSegmentationUI and only one time.