At Penn, the track is not announced until just a few moments before the train begins to board. This is ostensibly because the platforms are too small for people to wait on them, but it also has the side effect of keeping crowds up in the waiting area with all the shops.

The waiting area is on top of the escalators at Penn as well, but since you don't know which track you need to wait for, it is always a mad dash down the corridor for your train once the track number has been posted. This is made even worse by the fact that by the time the track number appears, there is only 3-5 minutes before departure of the train, so there is a sense of urgency required to get to the right place before the train leaves.

It is pretty terrible, but so is everything else about Penn.