According to HoopsTV.com, it is. Don't bother trying to go to the site -- it's no more. (For what it's worth, it was a great site -- all basketball, all the time. Featured great "And 1 style" videos, before they were big. Plus, it gave Tracy McGrady the nickname "The Big Sleep.") It was one of the (many) reasons I was academic probation after freshman year.
Anyways, I remember they used to say that this dunk was the BEST DUNK EVER:
A half-court, windmill-ally-oop IS pretty awesome, but...best ever?