To contribute to the original thread, the *A site also says this about Indian passport holders traveling to Mexico:
Originally Posted by *A.com
Visa required, except for A stay of max. 180 days:
- for alien residents of the U.S.A. holding proof of
residence;
- for alien residents of the U.S.A. holding a valid U.S.
Immigrant Visa.
- Effective from May 1, 2010 holders of a valid visa for the
U.S.A. will be visa exempt for a max. stay of 180 days.
I might actually go to Mexico now and see the pyramids at Teotihuacan.
Unfortunately, I do not see this backed up by an official Mexican government site.