I'm not a huge fan of Adam Gopnik, but in his most recent New Yorker piece (a review of a book on Times Square) he makes some very important points:

There are, of course, people who miss the old Times Square, its picturesque squalor and violence and misery and exploitation. ... Which just proves, as with the old maxim about belief, that people who refuse to be sentimental about the normal things don’t end up being sentimental about nothing; they end up being sentimental about anything, shedding tears about muggings and the shards of crack vials glittering like diamonds in the gutter.

One of my pet peeves in the media - bloggers included - are those who wax nostalgic for the "old Times Square," a stand-in for the pre-Giuliani city -sometimes otherwise phrased as "when the city had character," or "vitality," or some other intangible quality that ignores the massive amount of crime, breakdown and despair that were part of the "character" or "vitality" for anyone who actually lived in the city at the time. Even normally sensible people like Apt. 11D's Laura sometimes fall victim to this syndrome of inappropriate nostalgia. (And she's a Washington Heights resident - some areas of which, as I know from my sojourns to the inconveniently situated Yeshiva University, could still use a second helping of the Giuliani treatment.) Yes, gentrifying neighborhoods mean out-of-sight real estate prices, with the discomforting turnover. But it beats the hell out of landlords inviting drug dealers and arsonists to their properties to force out rent-controlled tenants, as was common in the 1970s. And blackouts from that era weren't nearly as fun as last summer's.

Nostalgia is often advertised as a sign of maturity and perspective. As often as not, it's exactly the opposite.