Labeling should be consistent whether the vector layer is rasterized or not. When the layer is rasterized, the labels are too. Its size and color is given by the tagging options, like in the 2D view.
On the other hand, when the vector layer is not rasterized, the labels will appear as floating text with the corresponding 3D objects for the data. Their size and color is again given by the tagging options.
Note: Only basic labeling is available in the 3D plugin.
