Between about 1964 and 1985 all street signs in Queens looked like this, with an off-white background and blue lettering. In 1964 the city installed large vinyl and metal street signs around town, replacing smaller enamel and metal signs that preceded them.
The city had started color coding signs in a haphazard fashion before 1964, but the codification was finalized when the new signs appeared.
Manhattan: gold with black letters. Ditto Staten Island.
[Staten Island had previously been using small gold and black signs, so this was likely a continuation of the policy, and not the actions of a little brother trying to emulate the big dog.]
Brooklyn: black, white lettering
Bronx: Blue, white lettering
Queens: off white, blue lettering
In 1985 federal guidelines stipulated that highway signs, including street signs, should be green with reflective letters. This was applied irregularly around the country, but NYC swiftly adhered to the ruling, and installed green and white signs everywhere, replacing the old color coded system.
Exceptions seem to have been granted for midtown (blue and white reflective signs) and downtown (black and white).
In 1999/2000, there were still a few dozen of the color coded signs around, but by 2011 their number has been whittled down to a precious few, like this one at little-trafficked 2nd Street and 55th Avenue in Hunters Point, Queens.