Tom Bridge asks whether we really care about our neighborhoods in DC. Maybe I'm not qualified to comment, as I live in Maryland, but my general thoughts are DC does care about neighborhoods... some neighborhoods. All one has to do is look at real estate listings to see how some neighborhoods are growing expansively large. Take Dupont Circle, for example. It's now grown to encompass pretty much everything South of V, West of 13th NW, East of the Park, and North of K. Now, certainly, Dupont is in that area. I'd submit that large swaths of that area aren't at all Dupont. They have character completely different from Dupont and aren't really there. I have a friend who lives at One Scott Circle NW in Dupont Circle. One might wonder how Scott Circle could be in Dupont Circle without being concentric, but apparently, in DC real estate anything is possible. I've seen places on U-St and 13th described as Dupont Circle, though being the location of the U-Street/Cardozo Metro station.
I suspect that soon enough D.C. itself will cease to the District of Columbia and just be Dupont Circle as it swallows the city whole like a real estate monster.