Snapped these pics w/my Blackberry this afternoon on West 53rd Street behind the Roseland Ballroom (click to enlarge):
While the "ring" around the sun is no doubt a photographic effect, I was more interested in the "lower" halo, like a rounded rainbow, seen most clearly above the right hand building, between the building on the left. One can seemingly see a series of halos closer to the sun itself, I'm not sure if that was an atmospheric or photographic effect.
Halos, I believe, are a phenomenon created by the passing of light throught ice crystals some 20,000+ feet up in the atmosphere. According to NASA, a daytime sun halo means the presence of ice crystals of "an exceptional gem-like quality".
I'll take that as a positive portent, especially over New York City....