From a distance, they looked like a legion of choreographed zombies. Marching in measured steps, their heads were all bowed at the same angle, gazes directed at palms they held rigidly at chest level.

On a busy Manhattan sidewalk, every single person coming my way was guilty of TWW -- texting while walking. Night of the Living Tweeters. How long, I thought, before I see the same thing in Minneapolis.

But it's already here, if not at such a notable concentration. TWW is not an offense we can be ticketed for, yet, but it is perhaps a crime against humanity -- our own-- to decide that being a pedestrian is just too pedestrian for our multitasking selves.

We work in posts to Twitter, Facebook and Foursquare while deleting spam and narrowly avoiding bashing into light poles, all before we reach the corner coffee shop. We may feel like we're not wasting a moment. But we are missing out on the random beauty around us. A world in which all eyes remain stuck on handheld devices is a world left unexplored.

See that albino squirrel make a mad suicidal dash into oncoming traffic? No? Well, in case you're interested, the pink-eyed little critter made it across the boulevard, and it was a much more inspiring experience than winning at Angry Birds. And speaking of inspiring, if your nose wasn't hovering 3 inches from your Droid screen, you might have noticed the flirty glance of a fetching passerby.

To illustrate the more absurd aspects of the TWW phenomenon, author William Powers cites an observation from this year's South by Southwest technology conference in Austin.

"These events are ostensibly all about meeting in person," said Powers, who wrote "Hamlet's Blackberry," a book about meaningful living in the digital age. "But many spend the whole time staring into screens, tweeting about all the new people they're encountering -- even as they ignore those same people in order to tweet about them."

Powers said he marvels at the assumption of many people that what's happening on their screen is more important than what's going on around them.

"Really? We've forgotten that the real world is, hands down, the most powerful source of information we have," he said. "Technology is fantastic, but ultimately it can't match direct human experience."

The most obvious issue with TWW, or even just listening to music on headphones, is that it can actually be hazardous to your health. In Long Island, a teen fell into a gaping construction hole because she was too busy playing thumb hockey on her cellphone. In San Francisco, a rash of muggings in broad daylight occurred while the victims were lost in textland. In Canada, a student was killed when his iPod prevented him from hearing a crashing helicopter headed his way.

At Hennepin County Medical Center in Minneapolis, anecdotal evidence is mounting that more patients injure themselves by tripping, falling or slamming into something while walking (or bicycling) and texting, said hospital spokeswoman Christine Hill.

"This last spring there was a rash of distracted walkers and bikers getting hit by cars, and one of the thoughts that arose is that everybody's plugged in and not paying attention to their surroundings," she said.

Over the summer, MIT social sciences and technology professor Sherry Turkle spent a lot of time walking the dunes of Cape Cod, as she has for the past three decades.

"People used to walk them like Thoreau, with eyes to sky and sea," she said.

"Now, no matter if they're alone, a pair of lovers, families with kids, everyone has their eyes glued to a device," she said. "When we do that, we miss the connections that count, with the people we love, with our physical surroundings."

Turkle, who wrote "Alone Together: Why We Expect More From Technology and Less From Each Other," stresses that she's not against deleting e-mails while, say, waiting in the grocery store line.

"But there's a cost," she said. "We have a different relationship with our community if we don't see the faces of the people in it, and we're not taking the implications of that seriously."

Technology researcher Jonathan Spira tosses another downside into the TWW ring -- while ambulatory texting might seem like the height of efficiency, it actually slows us down, he says.

"Each time you multitask, you're really time-slicing, compartmentalizing segments like slides on a carousel projector, with each slide representing a different thing," said Spira, whose book "Overload! How Too Much Information Is Hazardous to Your Organization" advances the theory that every time we interrupt ourselves, it takes us twice as long to get back on track with the original task.

His studies have found that the typical knowledge worker, or someone who is paid primarily to think, actually only has about 5 percent of the workday available to do so, deeply and without interruption. "When you're walking, you can use that time for contemplation, even relaxing and thinking about unimportant matters. We need that."

Powers, for one, manages to maintain a lighthearted attitude toward what he calls "smartphone blindness," saying that powerful new technology tends to bring initial enthusiasm along with "brow-furrowing" concern.

"After some bumbling -- and in this case, stumbling -- around, we always wind up figuring out how to live more or less wisely with the new gadgets," he said.

Until then, we'll all have to adjust to -- and leap out of the way of -- the growing number of walkers who lead with their foreheads.

"Someday we'll look back on this time and laugh about how silly it was that we allowed our devices to lead us around like a dog on a leash," he said.

Kristin Tillotson • 612-673-7046