There are very few companies implementing the newest features in varying amounts. Softimage comes to mind. But those companies are basically implementing them because of their close ties to the realtime-3D game market, making it faster for artists to preview their work without exporting to the game engine costantly. Some programs have used the transform unit, and almost all programs use either opengl or directx for normal viewport acceleration. I think for the average 3D program the pixel and vertex shaders now making their way into current videocards make more sense for a realtime 3D paint program, where the idea is to get a fast realtime preview of a texture effect. At least until ART cards get faster at hardware raytracing, or consumer cards reach that point. =)