In extended testing we found that we were not able to use one of the outputs from the Oak in the way we had used it on the prototype, so we removed it - there is only one version that was produced and that is the version we shipped. While shields generally change very little between prototypes and final versions, this was probably the most major change any shield received and we had no choice since that additional pin was useless as it had been connected on the prototype because the level shifter chip was holding it in state that was causing the Oak to not be able to boot.
We'll get schematics and board layouts up on the product pages as soon as the shipping/firmware rush dies down.
Thanks,
Erik