My initial thoughts here is that if this is real it would have been under construction for a while, and I find it hard to believe that Blizzard itself wouldn't have been saying anything about having theme parks under construction. Also given the somewhat touchy relationship between Blizzard and China over things like how much money they can make... I find this questionable.
Of course then again China *IS* a robber economy, and seems to pretty much steal almost everything from someone else, so it's possible that they robbed Blizzard's IPs and Blizzard doesn't want to give them free press by complaining.
I mean, let's be honest, we had that whole thing with China's knockoff Gundam (why they didn't thumb their nose at the Japanese I have no idea), and this whole "Joyland" name seems like a knockoff of Japan's "Joyopolis", including all the video game themed attractions.
This is not to say that it doesn't look like fun, because it does, it's just that it has to be taken with a grain of salt. If it is real, there are probably reasons why we haven't heard about it before now, and those reasons are liable to not be positive ones.
I mean I could be totally wrong, for all I know Blizzard is going to be screaming about this from the rooftops any day now, promoting "OMG, we have our own theme park attractions" and perhaps running contests with vacations to the park in China as the prize or whatever.
Honestly though, I will be very disappointed if it's real and there isn't a Murloc themed attraction.