The news of Starling City is on channel 'News 52' which is a nod to DC's New 52 comics.
The FEMA truck is number 52 which is a nod to DC's New 52 comics.
Oliver tries to convince Felicity to be his secretary telling her that he needs a "Girl Wednesday." She corrects him, saying that the movie he is referencing is "His Girl Friday." This could be considered a wink to the viewing audience, since "Arrow" airs on Wednesday nights.
Michael Jai White, who plays Bronze Tiger, also played a character named Gambol in The Dark Knight (2008); both franchises are in the DC Comics universe.