I think it can be useful for this conversation the first part of the second article of argentinian chapter's bylaws were we define free formats in a very sinthetic way[1]:
"The Association's goals are:
1. To actively contribute to the diffusion, improvement and progress of the knowledge and culture through the development and distribution of encyclopedias, collections of quotes, educational books and other document compilations; the diffusion of information and diverse data bases, especially in the languages spoken in the Argentine territory, which:
1.1. are available through technologies as Internet or similar, provided that: (a) the source of the data is available (for works resulting from the compilation or processing of other works), *(b) are given in a freely available format (defined as those that can be implemented by anyone, are based in publicly available and documented specifications, and whose implementation or use does not require the payment of any royalties), and the availability of the work is not restricted by technical measures*."
Patricio
[1] http://meta.wikimedia.org/wiki/Wikimedia_Argentina/Bylaws