In the example of Free and Open Source Software (FOSS), the term "free" does not necessarily mean that the software is FOC. It just means that the user has the "freedom" to modify the sourcecode. Applying this to OER, I guess the user has the "freedom" to modify the content. However, the means of modification (file format, text editor, video editor etc.) might not (or even need not) be free as in FOC. Furthermore the term "free" could again be an indication of "freedom" to use which ever means necessary or preferred to use and re-use OER.
In my opinion, access (i.e. being able to locate useful and quality OER) is much more important for the OER movement. I have an ulterior motive in saying this as I'm currently trying to figure out a way which can be used to locate useful and quality OER from the myriad of distributed, disconnected, incompatible and hidden sources of OER scattered throughout the world. However the lack of uniformity in referring, naming, attribution, file formats etc. poses a huge challenge to this. Maybe part of a possible solution would be to add the file format of the OER and the compatible software as a meta information to the OER itself. This will result in the potential user having the "freedom" to select which OER he/she wants to use. Ultimately it does not matter which file format an OER is published in but the quality and the accessibility of it. We will always find a way to open it and re-use it. If we are unable to do this then we have a whole different problem on our hands as it indicates a lack of access to technology or the lack of awareness of how to use technology (in my opinion of course).