PS4 being number 1 on Amazon America is really impressive since it is going in and out of stock. It looks like it is doing better than even in Europe at least compared to other video game products. Sony really nailed their launch.
As for the DS4 controller, it could be because the xbone is now readily available. Most people are probably buying it retail instead of absolutely anywhere it might be in stock like the ps4. If you look at previous years, the DS3 controller was always ahead of xbox 360s and ps3s on Amazon's best sellers. People are just more likely to buy accessories than consoles online.