"The signing of the four NJPW wrestlers, including Bullet Club members, is essentially a done deal as in 'agreed on the terms in principle' type of thing. The key to this matter now is how will WWE introduce these men as how they are initially presented will go miles into how they are perceived by the fans".
SOURCE: JRSBARBQ.COM (Check out his great writing)
It is a fair guess considering we have seen a bunch of stuff on WWE.com about these four guys already. A lot of people are saying that we will see one of them in the Royal Rumble. I know I will be extremely excited when these guys finally debut, whether it's in NXT or on the main roster! Love hearing from educated opinions like Ross who think the deal is essentially done though!