I saw it on the red carpet last night at the Oscars.  J Lo's nipple.  Is her name still J Lo?  Anyway,  I find it hard to believe that NO ONE would tell her that her nipple was showing.  In that dress, that's where your eyes go first.  Someone had to know!

Her stylist is saying it's just a shadow.  Are you buying that?  If you click on the picture, you can get a closer look.

I think it's a nip slip, and I think she did it on purpose to get attention.  I would rather fade into the background than get attention for something like that!