@Merry Andrew,
It means that the news articles below are OK for Orthodox Jews to eat (I.e. it's a joke).
"Taking Challah" is a Jewish religious ritual that is sometimes performed when bread is being made. A piece of the dough is separated and put aside while prayers are said. It is only performed if the flour used exceeds a certain weight: 2.2 Kg according to Ashkenazi custom, or 1.7 Kg according to Sephardic custom. Bread thus made is "Challah". A label "Challah is taken" may be applied to let the observant people know it's OK to eat.