Oh so very much, all in the name of the Rule of Scary. Among other things:

Anacondas are found in South America, not Borneo (on the other side of the world).
Anacondas get huge, but they spend the majority of their time in the water, only going on land if necessary. Water provides the buoyancy to allow them to grow massive.
The opening title crawl claims that anacondas grow up to 40 feet in length. While there are anecdotal accounts of anacondas (and other large constrictor snakes) growing up to 40 feet or longer which is probably what this claim is based on, most herpetologists consider this implausible ^note; there are reputable claims of anacondas growing up to 26 feet long, and an anaconda skin recovered from the Brazilian jungle reportedly measured 32.8 feet, but 10-15 foot snakes are far more common. Scientists believe that claims of even larger snakes may originate from skins and other remains that were stretched or distorted when preserved as well as general exaggeration and/or misidentification (some of the aformentioend claims get rather ludicrous, describing snakes of up to sixty feet or even over a hundred feet). There is at least one species of prehistoric snake which did grow that large, Titanoboa, but it went extinct about 58 million years ago ^note.
They do not move at the speed of a cheetah in chase. They can strike that fast, but not chase things that fast, even in water.
Folklore and anecdotes aside, there are no verified cases of anacondas consuming humans, although a snake 30-40 feet in length would certainly be capable of doing so.^note It is highly unlikely that they would actively stalk humans, though, especially after encountering life-threatening resistance each time.
They do not eat multiple preys the size of a human being, one after the other. After consuming a meal like that (which can take hours), the snake will find a secure location where it will remain immobile for months to digest its food. (Though the film may be playing that straight since there is more than one anaconda.)
They hiss, but they do not squeal/roar.
They certainly do not regurgitate their prey just so they can hunt again out of sheer sadism. They sometimes do this for safety purposes, such as when they are threatened by a predator and they can't afford to be lethargic by having such a big meal in their stomach, or if they find their meal is too big to eat.
The faces of the movie anacondas look more like the faces of vipers and other venomous snakes than actual anacondas or other pythons because the former look more intimidating.
Though some snakes have been known to do otherwise, anacondas don't swallow their prey while it's still alive. Studies have shown that constrictor snakes (including anacondas) are able to recognize a prey's heartbeat, and don't stop squeezing them until they feel it stop, and then they swallow it.

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