I don't have a particularly good source for it (that's why I asked for one!) but it's been all over the mainstream-ish news - just google "Manhattan UFO" within the next few days and you'll get a bunch of stuff. There's about five different videos of it on youtube last I checked.

Consensus pretty quickly seems to be that it was probably a balloon release, which may be why the weird news people haven't picked it up? I still think it's interesting in terms of thinking about how a truly unexplainable sighting over Manhattan would happen, though. Dunno, it's strange - the last couple big UFO flaps I've heard about have come to me through mainstream news rather than paranormal/weird sites. They seem to be rather out of fashion!