For the uninformed, the updated version of the gamepad features some slight changes when compared to the original model. One of which is that a strip on the top of the touch pad now lights up, which makes it easier for the PlayStation Camera to track in addition to being more convenient of the players to see the light bar indicator (which is typically use to identify players as well as show off the health status via different colors).
Another notable feature is being able to send inputs directly via the USB cable. On the PlayStation 4, you will have the option of using Bluetooth wireless or USB wired connections.
The updated DualShock 4 was previously only available as part of the bundle for the new PlayStation 4 slim model. The same pad is also included in the upcoming PlayStation 4 Pro, which is a more powerful version of the console designed to run compatible games better. So, if you are looking for a new PS4 controller, you might want to check out the new revision.