It is now about 1 month ago when Sony wanted to launch both systems in China. It has been cancelled at the last second and we don't know why... What happened?

China got some overly strict rules at last second and sony had to hold of the release

Well, the rumor is the following. China government must approve the games that will be released on the system. Despite that, they want the consoles to have region locks, so people wouldn't be able to import non-authorized games for that national system. That would be the reason why X1 is region locked in China.

We knew PS4 and Vita would be region free at China. The delay would be to add region locking to both consoles (China only).

The Chinese government interfered with the launch. We are probably not hearing anything until shortly before its launch.

I had a theory that Sony knew that they wouldn't be allowed to launch when they announced. They just wanted to put more pressure on the Chinese government to allow them to go region free. Also, I think they wanted to suppress the sales of black market knock-off systems and maybe even the XB1 sales.

Or, after removing the tinfoil hat:

They just didn't get approved in time....

Yeah I was wondering this too. Hopefully it launches soon.

I've been thinking about this too. Hopefully some news about it will come out shortly.

I also guess they didn't meet requirements from China and had to modify to whatever fits Chinese needs.
Xbox one also got delayed there, iirc.
I wonder if they can stick to their original plan of no region lock which was well received on forums.

I went to the Sony store in Shanghai about a week ago and tried some games. I also asked when the release was expected but all they could say was "shortly".

My own guess would be a launch in March, and that they will bundle Knack. Knack is the game they display as the front game.

They're trying to get Battlefield 4 approved as a launch game.