In my curriculum, surface embroidery in general and needlepainting are listed as separate modules. Now I have bracketed them together in one module only, called needlepainting. This is because I did a lot of general surface embroidery from the beginning of my stitching career. learned a lot of surface stitches part of which you can find in my stitchionary. So surface embroidery in general didn't have to be included in the curriculum.
When we think of needlepainting in the narrower sense of the word, we are thinking of long-and-short stitch. The projects which I worked in this module aren't exclusively done in this technique. They are actually done with surface stitches at least halfway through. Nevertheless, they are pictorial, that is very similar to paintings, so I think it is quite justified to call them needlepaintings.