Clearly this is a bug.

1. Go to Games -> Playstation

2. Go Playsation 4 -> Reviews

Bug: See that "The Legend of Zelda: A Link Between Worlds Review" shows up. Click it and see it's only for 3DS.

1. Go to Call Of Duty:Ghosts page.
2. Follow Call of Duty:Ghosts.
3. Add Call of Duty:Ghosts to a Stack.
4. Wait for a couple Call of Duty:Ghosts updates

ACTUAL RESULT: No notifications in my upper right dropdown for notification

EXPECTED RESULT: Some notification about the Call of Duty : Ghosts update shown in the dropdown.

*Note: Am I only the one seeing updates for any of their games show up?

I have the same thing. The Skyrim Hearthfire DLC update is the last update I see, though I always see the alert that I have new updates.