There appear to be two devices/detection capabilities being discussed here: An acoustic one to locate the source of a fired shot, and a laser one to locate the shine off of optics. I guess this latter can tell the difference between a flat piece of glass and a shaped lens.
I must assume that if this is getting print today, the USSS has had it for years.
Bingo! The was one of the obvious thoughts about this - how long has it been deployed already? How long was the F-117 around before they became widely known?
I agree about the two systems. Perhaps it uses acoustic to get a rough location, and laser to pinpoint the sniper's scope.
But I don't see how it can tell one curved lens from another: scope or eyeglass.