The hype campaign for this movie has been pretty big in Japan. There's been posters, leaflets, the obvious things like trailers and other content but some of the publicity stuff has been a little strange. For example, there's an instagram account called Kayako With Toshio which pictures the evil duo from The Grudge in rather mundane settings such as seeing Toshio off to school or having noodles.
Even stranger than that was a TV segment during a baseball game where the two characters were put on the field to face off in a spot of batting and pitching.
One thing you have to understand about Japanese horror movies, especially of this kind, are very formulaic. Usually they are stories about a curse or some kind of rumor going around, then the hero gets cursed and some fucked up shit happens. Following that, they find someone who is super knowledgeable about said curse and they proceed to enact some insane plan in order to remove the evil ghost from the persons life. It's not a bad formula but it's so played out at this point that when a new movie does it the only thing you can really gamble on is if its going to be a happy ending or an everyone dies ending and everything before that you could predict like the worlds best clairvoyant.
However, while Sadako Vs Kayako does this for it's first half, once it gets it's boring shit out of the way it flies completely off the rails into insanity. Luckily, the stupid shit that goes down after the movies half way mark isn't the kind of stupid shit that makes you sigh and rolls your eyes but it's the sort of awesome stupid shit that has you holding back cheers of joy, sort of similar to the reaction you have when watching an Expendables movie. I can't do it justice without heavy spoilers but please, do yourself a favor and go watch this movie, you won't regret it for one second.
I think most people, like me, weren't expecting a lot from this movie so it ends up being a pleasant surprise. Don't take it too seriously and just sit back and enjoy the roller coaster of retardation that is Sadako Vs Kayako.