I don't understand the point of the light bar to be honest. If it's to be used for additional info, whilst I'm playing I'm looking at the screen not the controller! Also, from the looks of the pictures, you can't see the lightbar when holding the controller as if you are playing.
The headset jack may seem redundancy since I'm sure a lot of gamers are using wireless headset. To me, I think it is brilliant. It will become handy if the battery life of the controller is managed properly. The internal speaker is another excellent feature.
I wonder whether PS Vita or next generation PSP can be used as a controller for PS4 just like PSP with PS3. There are a lot of touch capability on PS Vita. I am sure it will open up a lot of in-game feature.