From the previews, it looks like the original, except for the following:
GOOD
1. Better looking characters, explosions, and effects
2. More missions, cut scenes, and does a better job explaining how everything works.
3. Larger number of people and vehicles on screen at once.
4. Higher resolution / cleaner textures
5. More variety in businesses
BAD
1. Scenery is not much improved from current gen.
2. Gameplay is relatively unchanged from current gen versions. No need to buy if you already played it on XB1 or PS2.