Recently I came across a few articles related to the new High Line section opening. I already noted to see the High Lane next time I'll be in New York, so I had a look at these articles. Inhabitat has a great article, with video including an interview of the landscape designer. Also the press across the world reported that opening.
I find that very interesting, because... Who would think a refurbished railroad would provoke such much enthusiasm and curiosity across the world? Just because it's in New York? There are many parks in New York and no one mention them outside the city boundaries (Tompkins Square anyone?).
So there must be something else. One is that the design is really modern and ambitious, with very well designed paths, vegetation everywhere, places to socialize. Another one is that it is higher than the rest of the streets, giving a new view on the city - and New York is probably one of the very best places to make use of good perspectives!
Also it is not really a park - it is more a way, making de facto a pedestrian street in New York, which is definitely not common.
(image from Wikipedia)
So in many sights, the high lane is really innovative. So what if others could cities could take inspiration of that? In my town for example, there is a big debate about doing a stair between the river and an former hospital from the middle age, building a whole new path above the historical city wall. I think that is a wonderful idea, as it will create a whole new street in a town quarter that hasn't seen much new streets in the last 500 years.
Creating such attractions also makes people curious, and make them come there. It's not needed to say that many city centers need to attract people back. That won't happen without changing anything. By reusing the existing infrastructure and being creative with it, magic things happen.