There is certainly something to be said for wide open spaces in cities. Large, well-designed parks are a welcome respite from the high-energy city streets. They are perfect for jogging, biking, and walking. They make great places to take children to play. They are often as close to nature as many urbanites can get on a daily or even weekly basis.
That being said, I think that people tend to blindly value "open space" without any consideration for quality. In another example of the public's fear of density, NIMBYs are often quick to cite the loss of "open space" as a reason for their opposing a new structure. I remember, when I was living in Milwaukee, a group of "concerned neighbors" trying to get plans for a high-rise condo building in the heart of downtown scrapped because it was going to destroy what they called open space. In actuality, the lot was a glorified traffic island. Also, it was across the street from one of the city's largest parks, which in turn fronted the great blue expanse of Lake Michigan. A loss of open space? Technically, yes. But the city certainly traded up.
The anecdote neatly illustrates what I think is a major semantic issue that gets little to no attention: people have idealized "open" space when what they should really be focusing on is "quality" space. After all, the endless expanse of cornfields in the Great Plains states are technically open space, yet seemingly everyone who's driven through them is jumping out of their skin to tell you how awful the drive is. The same goes for Atlanta's infamous eight-lanes-in-each-direction megafreeway, which I had the displeasure of traversing (fancy word alert!) in the shuttle to my hotel this afternoon. It struck me as very odd that a city of only 130 square miles would waste such a massive chunk of their land on this non-place, which is essentially a large "open space" that is used by millions of people every day yet is completely devoid of character or any sort of sense of place. But then...that's another post entirely.
When the distinction between "open" and "quality" public space is ignored, it allows not only for the types of ridiculous arguments used by the "concerned neighbors" mentioned above, but on a more subversive level it devalues public space in general. If we continue to dilute parks, squares and the like by lumping them in with plain ol' "open spaces," they lose their importance in the cityscape. Sure, it's a word game. But you'd be surprised how much those can matter.
"Urban Renewal," anyone?