Notice the tail of ISON doesn't point away from the Sun when it leaves the Sun like other comets do. If it doesn't quack like a duck, is it a duck? Or is it something else? Something rather special? :)
PS: My daughter the aspiring astrophysicist student sent this reply to me about the strange tail...
"Actually a comet has two tails: the dust tail and the ion tail. The ion tail goes in the opposite direction of the suns magnetic field, but often what's visible is the dust tail since the dust reflects the light back on us from an observing point of view. I think the dust tail is also probably following the motion of the nucleus. Ison is an odd comet and they all behave differently. It's hard to draw a conclusion without seeing the soho images and the data..."
Tthanks to: http://americankabuki.blogspot.com