Top-grossing indie producer, Jeff Most, who is developing a U.S.-China co-production based on the best-selling comic book, Razor, told Xinhua, "It's a bit of a shock it's finally happened. We all knew the China market was a huge and important one, but this day just came sooner than anticipated."

"It's still the biggest of (foreign) markets where we or any studio does business," said Dave Hollis, Disney's exiting global distribution chief, "and it will still be on pace to displace the U.S. in the box office."

"Though this No.1 ranking represents one isolated quarter at this point, it's going to be permanent before you know it," predicted Ms. Li.

But China still has a way to go to solidify its reign as box office No.1 in the world.

Using the last quarter exchange rates of 2017, China's $8.6 billion vs Hollywood's $11.1 billion still shows a 22.6 percent spread between the champion and its runner up.

While U.S. grosses flagged 2.5 percent in 2017, down from 2016's all time high of $11.4 billion, they nonetheless squeaked across Hollywood's $11 billion goal post for the third straight year in a row, beginning with 2015's $11.14 billion, which gave many in Tinseltown a sigh of relief.