The real link is www.ancestry.com/Mexico
This is great news for anyone hoping to have success in searching for anyone with Mexican Roots.
This got me wondering if the LDS Church - FamilySearch.org also has the Mexico Federal 1930 Census online and it appears that they do have it online.
According to a Blog Post by Dianne Haddad of Family Tree Magazine the Church finished this project first and has had the Mexico Census up in its entirety since May 2011.
Dianne also posted another post today about this new development and has some great info there.
I'll also point out as Dianne did the great book by George and Peggy Ryskamp Finding Your Mexican Ancestors: A Beginners Guide
In 2005-6 I studied Genealogy at BYU and took a three month trip to Spain with the Ryskamps and its one of the highlights of my life. They are very knowledgeable and just wonderful people in general. If you ever get a chance to meet them at a conference or while they are researching in another country count yourself blessed as they are the cream of the crop when it comes to genealogy research experts.