Mexico is making two major changes this year to aim for total e-invoicing. The first one is termination of the CFD model and making CFDI adoption mandatory. This means that suppliers will no longer be able to create their own electronic invoices but will have to work with a service provider. The other one is reducing the minimum annual income level required for companies to comply with the Mexiacan e-Invoicing mandate is USD 150,000.
Source: http://www.ob10.com/OB10Blog/post/2013/04/26/Mexicos-quest-for-total-e-Invoicing.aspx