The decision to mandate data deposition as a condition of publication is another decision best made by the scientific community concerned rather than a single journal or publisher as, for example, has been established in the microarray and evolutionary biology communities . We will, therefore, support data publication when it is mandated, but will also enable, encourage and recognize  data sharing and publication on a voluntary basis for scientists wishing to show leadership in their field.Now, as the journal already allows reuse of papers (CC-BY license), this also applies to data (and in at least several countries data cannot be copyrighted at all, but we need a world-wide solution; it's the 21st century). However, earlier this year the Panton Principles were introduced which formalize the idea behind public domain waiving, and suggest the CC0 waiver as one valid approach. This is where BioMed Central wants to go too; they write:
All research articles published in BioMed Central journals are published under the Creative Commons attribution licence  (CC-BY), with which authors retain the copyright to their work. This licence allows unrestricted distribution and re-use provided that the original article is cited. We support the Panton Principles for open data in science  and open data should therefore mean that it is freely available on the public internet permitting any user to download, copy, analyse, re-process, pass them to software or use them for any other purpose without financial, legal, or technical barriers other than those inseparable from gaining access to the internet itself. We encourage the use of fully open file formats wherever possible.The above quoted text are extracted from the draft, and your comments are most welcome. You can leave them as comment here, which I strongly encourage you to do. If even just to support the idea (see McPrinciple3).
Therefore, to eliminate potential legal impediments to integration and re-use of data, specifically, and to help enable long-term interoperability of data we believe an appropriate licence or waiver specific to data should be applied, and made explicit by the authors and publishers. There are a number of conformant licences  for open data, of which Creative Commons CC0  is widely recognised. Under CC0, authors waive all of his or her rights to the work worldwide under copyright law and all related or neighboring legal rights he or she had in the work, to the extent allowable by law.
The draft also touches the issue of Open Standards, but I feel this problem with resolve itself. More interestingly, it is now time for the journal editors to make a move, and let the community know if they will require these open data waivers for there journal. For example, cheminformatics as field would benefit very much if the Journal of Cheminformatics would make this move. But at the same time, I fully understand that a young journal may not yet be in the position to do just that yet.