Keri and Sky, will a wedding happen here?

Is saying something on the radio legally binding? Earlier in June, Keri Miller and Sky Tshabalala said that they will marry each other if Darren Maule married Anna. Now Darren married Anna and avid listeners are wasting no time reminding Keri and Sky about their promise. They had a bit of an argument and Sky announced that he has a girlfriend all of a sudden, but, rest assured, this debacle is far from over.