For some reason, people go ape shit for Discover Channel's Shark Week. It's like a serious deal, for which people will turn down party invitations. We don't get it, but we also don't judge. People are so obsessed with Shark Week, they dress their buildings up in homage.
It would be weirder if this building were not the national headquarters of Discover Channel, located in Silver Spring, MD.
More architecturally knowledgeable and inclined folks, over at DCMetrocentric pointed out that the shark outfit is cleverly placed in such a way that uses an aspect of the building as a fin.