Hi Cheryl. Your friends must be sitting pretty now, with the peso down to 16 1/2 to the USD! Our family is in Norway, whose currency had fallen even quicker than Mexico's, over the past six months. So, it's nice to have one's savings in USD.
By the way, that "International Man" site I recommended before: it has abandoned its forum, so isn't really worth bothering with now. Pity!