BURLINGAME, CALIF. — Kids have it so good nowadays: A new animated movie to entertain and delight them is always playing at a neighborhood multiplex.

Indeed, the number of animated feature films has skyrocketed in recent years. In 2008 alone, 20 animated movies played in theaters, and they rang up more than US$1 billion at the box office, according to data from Nielsen EDI. The futuristic "Wall-E" was the highest-grossing animated film last year, taking in $224 million; the lovable "Kung Fu Panda" followed with $215 million in ticket sales.

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Several animated movies, including "Coraline" and "Monsters Vs. Aliens," have been released so far this year, and several more, including "Up" and "Ice Age: Dawn of the Dinosaurs" are slated for summer.

Advancements in animation technology and consumers' insatiable appetite for stylized robots, animals and monsters have propelled the industry. The momentum isn't likely to slow down anytime soon, industry watchers say.

"If you look worldwide, there are 45 or 50 fully 3D feature-length, computer-animated films in production today, ready for release over the next couple of years," says Terrence Masson, an industry veteran who has worked at George Lucas' Industrial Light & Magic and consulted for Disney and DreamWorks.

Animated movies aren't just for kids anymore. Adults are flocking to theaters as well, as storylines have become more mature. "The creative ambition is now matched by technical capabilities; the sophistication of the imagery now matches sophisticated stories," says Ann Daly, chief operating officer at DreamWorks, the studio behind Shrek and Madagascar.

Animation is so pervasive now that some form of it winds up in most live-action films. "Technically, anything [in a movie] is animation if it didn't happen in real time," says Chuck Sheetz, a professor of animation at the University of California, Los Angeles. "In Spider Man, when he's swinging along, it's an animated character mixed in with live action."

Richard Weinberg, a professor at the University of Southern California's School of Cinematic Arts, agrees. "Almost everybody is using some form of animation to tell their story," he says. "Now there's a fuzzy boundary between live action and animation."

Now that movie studios have so much powerful animation and computer graphics technologies, they also need to be judicious in how they use them. Sheetz says action sequences are often too long now because studios want to wow audiences with technical wizardry, but this doesn't always help the movie's storyline.

"If something goes on for too long, it dilutes the impact of what you're trying to get across," he says.

Despite all the advances in animation and computer graphics over the past 20 years, making an animated movie is still hard work, involving hundreds of people and often costing upwards of $100 million.

"The technical challenge is not the problem," says Ed Catmull, president of both Pixar Animation and Disney Animation. "The problem is that the artistic part of every process is a major component and you have to get them all right. It's that corralling of creative forces and guiding those forces that's hard."