That's a good question. A question I have pondered over the last several months. Every week I wait and see how far the value of a USD is, it just keeps getting lower so I've been withdrawing large sums of money from the ATM and glad I did because it's gradually going down down down.

It's quite noticeable now if you live in Mexico, but visiting it's not really a big deal in my opinion unless you're staying in a upper tier hotel resort on the beach paying in Mexican pesos, then you'll get hit pretty hard. Here's a chart, so your guess is as good as mine.