They are marketing images, nothing to do with video
— Guilherme Rambo (@_inside) August 31, 2018
Check out the image below:
What we see is an Apple Watch which appears thinner, plus with a larger edge-to-edge display, showing more details than ever before on its watch face with numerous complications, now totalling 8, according to the picture.
The new Apple Watch Series 4 looks to be able to fit existing watch bands, while below the Digital Crown (which now has a single red ring to indicate LTE?) there appears to be another microphone. This looks like the Apple Watch people have been waiting for.