I recently participated in a study for the FDA on the issue of gluten-free product labeling. It was very interesting and I'm so glad to have been a part of it. They asked questions about pictures of GF labels that they showed us for the "most" confusing and "least" confusing- and which ones we had more confidence in.
Go to this website, and mid-way down the page, see "Gluten-Free" where you will find the FDA's proposed rule to define the food labeling term "gluten-free" and a Q and A about this proposal.
They told us to keep checking the website for updates (the last posting was from 2007!! so hopefully there will be some updates now in 2009-2010!) We were also told that in the near future, the FDA plans to publish for public comment a Federal Register notice announcing the availability of the agency's safety assessment on gluten exposure in individuals with ceilac disease. Sometime after the comment period on this safety assessment closes, the FDA will issue a final rule defining the term "gluten-free"!