The back-story to the Mexican AM decision is interesting.
AMs in that country (like the ones here) are having a tough time economically, as FMs have most of the audience and ad revenue. Word is a group of smaller, independent broadcasters around Mexico City broke away from the large broadcast association and pushed for this. The group was successful in getting the attention of the government and got the large broadcast association to go along.
As this change plays out over the next three years, it will be interesting to see the effect on U.S. border stations.
In the same document, the government gave itself until Sept. 15, 2009, to choose a digital radio standard for the country.
Mexico last year began allowing stations within some-200 miles of the U.S. border to use IBOC on an experimental basis. I hear some 12 stations — both AM and FM — are doing so.