More 30 mph speed limits on neighborhood serving arterials in DC
Granted these roads are the classic definition of principal arterials as connecting activity centers and therefore carrying a lot of traffic. But at the same time these are pedestrian-centric residential areas as well, although that's more true for Wisconsin Avenue than Nebraska Avenue.
I was traveling yesterday in this part of the city in a car and was watching for the signs.
3000 block of Wisconsin Avenue NW (the speed limit changes to 25 mph just south of Massachusetts Avenue, but it's 30 mph, I think to the DC-MD line)
Nebraska Avenue, approaching Connecticut Avenue from the northeast (I'm not sure how much of the street is 30 mph, I think it goes back and forth between 25 mph and 30 mph)
... which makes the current version of the StreetSmart "pedestrian safety" advertising campaign all that more ironic. (As with the last few campaigns from this program, I am unimpressed with this campaign too. I may write about it... See "Being Direct in Advertising: Pedestrian Safety.")