Is there a part missing?
Is it just me as a Samsung noob or is there a part missing?
Please click the picture to get a better view of the phone.
@stijntech that looks like connector HDC4000 which is supposed to connect the flex cable for the proximity sensor/Mic/service LED connector. So no part missing on the board. Your image is not clear enough (repeat straight down instead of angled) to see if the flex is there.
The part that is to be plugged in there is the sensor for your proximity sensor, light sensor, and LED.
The part looks like this: http://www.ebay.com/itm/OEM-T-MOBILE-SAM...
Perhaps it's there but the flex ribbon is just under the board, it happens to the best of us trust me lol. Just lift the board up and it might be there, if not just buy a replacement. All it is is just a snap on connector no biggy.