A breakthrough in the final hours of Xi Jinping's US tour has eased restrictions on imports of US films into China, and could lead to more 3D and Imax films being made in Hollywood.
Major American studios and independent film-makers alike are celebrating the deal to settle a long-running trade dispute, struck by Joe Biden and Xi.
The two national vice-presidents agreed the deal over dinner in Los Angeles on Friday.
China currently permits only 20 big foreign films a year to be released there, to the frustration of US studios. The pact allows in an extra 14 films each year, provided they are in Imax or 3D formats.
It also allows foreign film-makers to keep a bigger share of box office takings: they will receive 25% instead of 13%.
"This is a very big deal," said Chris Dodd, chairman of the Motion Picture Association of America.
"The industry has been living with the numbers in terms of percentages and quotas for 20 years … it begged for a conclusion."
Though the Hollywood films released in China are few in number, they account for about 40% of the country's box office takings.
China's film world has reacted with caution, with directors, cinema operators and film critics saying extra foreign films will squeeze domestic producers, but may ultimately raise quality.
In 2011, the total value of China's box office was more than 13.bn yuan (£1.3bn). Of that, foreign releases took roughly 6bn yuan, according to the state administration of radio, film and television data.
"The box office of domestic movies will definitely be impacted, which means Chinese movie-makers have to work their butts off to improve their competitiveness," said Yuan Xin of cinema operator Stella Mega International group.
Domestic critics regularly berate China's film-makers for failing to produce movies as popular as US ones.
Particular criticism was fomented by the stellar success of the first Kung Fu Panda film, a runaway hit that used – or, some said, exploited – Chinese themes.
Su Mu, a professor at Beijing's film academy, said: "More and more [Chinese] movies are not focusing on the story and plot but relying on big stars or promotion stunts to 'deceive' audience into theatres.
"More US movies may force domestic producers to take a correct attitude toward their works and learn from others."
However, market trends suggest that blockbusters are exactly what Chinese audiences want.
Many of the nation's new cinemas – an extra 803 theatres opened in 2011 – are equipped for Imax and 3D.
Recent big Imax or 3D hits included Avatar, Mission Impossible – Ghost Protocol and Transformers: Dark of the Moon.
Nonetheless, US independent film-makers also see the new agreement as a milestone for revenue-earning opportunities in China.
"We do think it's a breakthrough," Jean Prewitt, president of the Independent Film and Television Alliance, told the Los Angeles Times.
"For the first time we really have the building blocks to begin to work competitively in that marketplace," she said.
Independent producers will now be able to negotiate fixed licence fees at similar percentages to those they would get elsewhere, rather than the 2% or 3% of earnings typical now.
About 40 foreign independent films get releases in China each year, outside the quota of 20 big studio films.
The US complained to the World Trade Organisation about China's quota in 2007, and won a favourable judgment in 2009.
Xi and Biden agreed the new system can be reviewed in five years.
