'Avengers: Infinity War' is officially a billion-dollar movie

Avengers: Infinity War hit yet another box office milestone this weekend.

On Saturday, the latest Marvel Cinematic Universe adventure crossed the billion-dollar mark at the worldwide box office. It took just 11 days to reach that point, faster than any other film to date.

It's Marvel's sixth billion-dollar movie and Disney's seventeenth -- meaning the studio's releases now officially account for half of the 34 movies to ever hit $1 billion at the box office. The weekend also makes Infinity War ($1.16 billion) the #5 super-hero movie of all time at the global box office, behind four other MCU releases.

In the U.S., the latest Avengers took in an estimated $112.5 million during its second weekend. It's only the fifth film in Hollywood history to makes more than $100 million in its second weekend. Perhaps even more impressively, the overall domestic box office of $451 million makes Infinity War the #15 highest domestic box office earner of all time.

This is a popular movie.

The question is, will it last? To use a current example, Infinity War audiences are so far drifting away faster than Black Panther moviegoers. Roughly 56 percent of the audience dropped off from the first weekend to the second, compared to a much smaller 45 percent for Panther.

That said, we only have a small sample size to work with so far. The big test for Infinity War's ultimate box office performance will be how it fares in weeks three, four, five, and on. It has a good shot at topping Black Panther's domestic total of $693.1 million (and counting, as the movie is still in theaters), but nothing is assured.

For one, Infinity War is a long movie. At two hours and 40 minutes, it's got the MCU's longest running time to date. That kind of time commitment -- especially when you factor in trailers, ticket purchases, and schlepping to and from the theater -- only hurts the prospects of the audience signing up for repeat viewings.

What's more, Infinity War is only half of a two-part story while also serving as the culmination of an arc that the MCU has been building up to for the past 10 years. For all of its positive qualities, it's an unwieldy beast that lacks any sense of immediate closure.

Compare that to Black Panther, a relatively self-contained story with a clear beginning, middle, and end. Its ability to stand alone also means it has much broader appeal, as audiences can walk in knowing they don't need 10 years of movie history in their head to fully enjoy what they're seeing.

Beyond all of that, it's also the spring/summer release season: Infinity War is weeks away from competing with mega-blockbusters like Deadpool 2, Solo: A Star Wars Story, and Jurassic World: Fallen Kingdom. Meanwhile, Black Panther -- a February release -- had a clear runway for more than a month before any viable competitors came along.

None of this is meant as a knock on Infinity War, which is a great Avengers movie in its own right and one that serves the fan community well. But there are plenty of obstacles to Infinity War reaching the domestic box office success of some of its predecessors.