New York City takes a big step to save lives on the streets, but not everyone wants to slow down. And Twitter's proposing a way to keep its employees separated from the regular people of San Francisco, at least while they're at work. It's What's Ruining Our Cities!

The 25 mph speed limit is not ruining New York City

As part of Mayor Bill de Blasio's Vision Zero plan to end traffic deaths, New York City implemented what might be the most noticeable change to residents on Friday: The citywide speed limit is now 25 mph (highways, of course, will remain their speedy selves). This is a groundbreaking move that puts NYC on par with other pedestrian-first cities like London and Paris, plus it's backed by pretty simple science: If you get hit by a car at 25 mph, you're 50 percent less likely to die than you would be if that same car hit you going 30 mph. Yet in what has got to be the stupidest response to the news, the New Yorker's Nick Paumgarten bemoans the change as the latest ploy by de Blasio to demonize the car, going so far as to reminisce about the culture of bad driving in NYC: "The wickedness of the automobile, and of anyone who would be so crass as to operate one, is a central tenet of contemporary urban planning." Wow, he's right, driving recklessly is so New York. Be sure to tell that to the 286 people killed by cars in the city last year. [New Yorker]

Twitter is ruining San Francisco

I know, there is a pretty good argument to be made that Twitter is always ruining San Francisco. But in this case, it's not as much the mindless microblogging drivel as it is the company itself. When Twitter moved into two buildings on busy Market Street in San Francisco instead of some far-flung suburban site, they were lauded by urbanists (and welcomed with tax breaks from the city). But now Twitter's losing that clout: The company has proposed a skybridge that will allow employees to walk from one building to the other without having to go down to street level. While the company claims it's for efficiency (a statement says it will save employees "up to five minutes") it's a move some say is specifically designed to avoid potential unsavory interactions in the transitioning neighborhood—and creates the same kind of insular Silicon Valley campus in the center of town. [SF Chronicle]

Paint is ruining Berlin

The Berlin Wall came down 25 years ago today, heralding a rebirth for one-half of a city crushed by Communism. Yet well into the 1990s Berlin was still trying to find its footing in a post Cold War-era, until creatives began occupying its abandoned warehouses and transforming its storefronts. The new book Berlin Wonderland recalls the heyday of this freewheeling time for the city, as it became a playground for artists. But some say the change has gone too far and are nostalgic for the time when art still ruled the streets. Gorgeous then-and-now photos show the swift transition in this BuzzFeed slideshow. Do you prefer the graffiti-coated Berlin or the Berlin with its smooth new layers of memory-erasing paint? [BuzzFeed]

Top image: Spencer Platt/Getty Images