Yes, my favourite Music Store has it listed as discontinued, but it is still listed on the Korg UK website.
There has been much speculation over on the Korg forum of new models.
A new Kronos for one and a new Pa4X for another.
Whilst the Kronos is arguably still the King for its users the Pa4X has the Yamaha Genos to contend with and it is swings and roundabouts as to which is better.
The other Pa models now have the Yamaha SX models to contend with which are a vast improvement over the S models so even though both are only just over two years old a refresh is badly needed in the operating system, functions and releasing more available onboard memory.
Me, I am hoping for a revised Pa4X with updated hardware and all my current keyboard hunting and check outs are leading up to what is released at NAMM.
That said if I get a good deal on my keyboards then I may well get a Pa4X and then if a successor to it is auditioned at NAMM then I will do a Kaneda with it.