It appears WWE has moved from "the big four" pay-per-views to the "big five."
Money in the Bank will now be a co-branded pay-per-view show, highlighting talent from both Raw and Smackdown Live moving forward. Fightful has spoken with multiple people within WWE about the decision and what went into it.
With a major void in co-branded shows between WrestleMania and Summerslam, the idea was pitched to utilize the Money in the Bank show to help bridge the two. However, specifics about the number of Money in the Bank ladder matches or competitors haven't been solidified as of yet, and likely won't be for several months.
This will have implications on other WWE PPV shows as well, with "Great Balls of Fire" being axed from the schedule. The name of the show was a Vince McMahon idea and was widely criticized by fans, media, and many within WWE.
In 2016, the Money in the Bank show was a Smackdown-exclusive, and there were only four co-branded shows -- Royal Rumble, WrestleMania, Summerslam and Survivor Series. There were pitches to do have six co-branded shows, as well.
You can see the full WWE PPV schedule for 2018 below
Royal Rumble January 28 Philadelphia, PA
Elimination Chamber (Raw) February 25 Las Vegas, NV
Fast Lane (SD Live) March 11 Columbus, OH
WrestleMania 34 April 8 New Orleans, LA
Backlash (Raw) May 6 Newark, NJ
Payback (SD Live) May 27 Baltimore, MD
Money In The Bank June 17 Chicago, IL
Battleground (Raw) July 15 Pittsburgh, PA
Summerslam August 19 Brooklyn, NY
Extreme Rules (Raw)September 16 San Antonio, TX
Hell In A Cell (SD Live) September 30 Nashville, TN
WWE TLC (Raw) October 21 Boston, MA
Survivor Series November 18 Los Angeles, CA
Clash Of Champions (SD Live) December 16 San Jose, CA