One for profit organization - NYCRuns and One not for profit organization - NYRR
I'll be honest that I've run both companies races and do prefer NYRR's races as they seem to have better courses and I can also see how someone who might not be a NYC area runner can easily get confused being that the race dates are 3 weeks apart.
I don't know of any race that has only a one word difference the name of it and that being the title sponsor... Seems kind of sus to me and perhaps NYCRuns didn't think it through and if they did they accepted the uptick in registrations because of the confusion.