I'd say the PS4 is around 11.4 - 11.5 by now, and 178k seems very low following the huge Destiny week, especially when you consider how the Destiny bundle has still been doing very well in the Amazon charts. I expected around 250k this week for the PS4 + the undertracking of the PS4 seems to have continued and we're still missing around 200k from the last big adjustment.
The PS5 Exists.