As with many beta products, changes can occur and wouldn't you know it, the Steam Controller has changed from its initial iteration. Engadget has the picture and word that the touchscreen that was going to be on the top of the controller has now gone away and instead there will be buttons.
The buttons are actually below the two touchpad like controls, which to me seems a little awkward. No word on why they removed it, but who knows. Things could change again before the final release and there are going to be third parties that design their own Steam Controllers as well. We might see one with a touchscreen from someone.