Premises: if they announced the upcoming season 4, it means they are already working on it (even if we don't know the staff, yet).
When I looked at this pictures for the first time, I thought it was just a slight change from season 3.
BUT, the more I look at this, the more I realize the changes aren't so “slight”:
- the eyes are totally different both from season 1-2 and season 3, not just the way they are drawn but also the proportion eyes/face (the new eyes are bigger!). We have already seen these new eyes in some other recent commercials, and since I don’t think these new eyes are going to be used just for some commercials here and there, I assume these eyes are the eyes we will see also in season 4: totally new eyes (the best ones, in my opinion: better both than season 1-2 and season 3)
- the mouth is far smaller. No lipstick, but definitively smaller (like season 1-2).
- the nose is smaller and better defined.
- No more lucid spots on cheeks? The excessive shining of season 3 (lucid spots plus eyes) seems definitively gone.
- Colors are far more vivid and not “sort of washed out” as season 3: again, a moving back to season 1-2.
- In the last picture, even if really small, Usagi’s pigtails look a bit different: less thin and a bit more curly (again, back to season 1-2′s style?).
Overall, the changes are an improvement.
Now, we have some options.
OPTIONS 1: season 4 won’t be a total change from season 3 but an improvement. In this case, there’s the chance that the new BB’s commercial is actually the style of season 4. Just an improvement of season 3.
OPTIONS 2: season 4 won’t be a total change from season 3 but a mix of season 1-2 and season 3. In this case, besides the totally new eyes, the smaller mouth and more vivid color can be a hint of this mix, but BB’s commercial isn’t the style we will see in season 4, yet (close, but not the final style, yet).
OPTIONS 3: season 4 will be a total change from season 3 (the way season 3 changed from season 1-2). In this case, BB’s commercial is just a vague hint of the changing: the new eyes, more vivid colors and smaller mouth…. among many other changes (Usagi’s pigtails and skirts… not showed, yet).
We must wait for the fist visual of season 4.