It is clear Samsung is referring to the Galaxy Note 4 as you can observe at the right up of the invitation. (Air commands). Just compare with the picture below of the Galaxy Note 3:
The questions for the Galaxy Note new version 4 are: Size of the screen, Processor, battery, Camera and we suppose a bigger device size, a new processor speed, a better battery and more pixels for the camera. A Flexible display might come in and maybe some new software features. Will see those in Sept 3.