Don't worry. The National Cathedral isn't collapsing.
It is, however, losing a few chunks of rock. According to Dean Sam Lloyd, one of the stone finials on top of the cathedral's central tower fell off—meaning the highest point in Washington just got a little lower—and there's evidence of a couple small cracks in the flying buttresses (that's external arches to you, heathen). But after a first walk through, the interior seems to have survived intact, even all those stained glass windows. A chief mason will do a full check tomorrow, and the cathedral remains closed to the public in the mean time.
"It's looking like only modest damage," Lloyd says. "This was the kind of thing that can be very serious."
Can be! While older cathedrals in the older nations of the world have weathered worse, this is the first time the relative toddler of a building (construction only finished up in 1990) has experienced any significant shaking. Unlike some modern cathedrals, this one was built without an internal steel skeleton; all the masonry simply sits on top of itself.
"At least so far, indications are that the building can withstand a fairly significant tremor," Lloyd says. Whew!
UPDATE, 5:17 p.m. - The National Cathedral sent out this more complete accounting of the damage:
Three of four pinnacles (corner spires) on the central tower have been damaged. Specifically, three "finials" (capstones shaped like fleurs-de-lys) have fallen from them, with more significant damage to two of the pinnacles. Similar decorative elements on the Cathedral's exterior also appear to be damaged. Cracks have appeared in the flying buttresses around the apse at the Cathedral's east end, the first portion of the building to be constructed, but the buttresses supporting the central tower seem to be sound.