This is purely cosmetic, but would save a few brain cycles every time I go to download images. Any time I plug the SD card into my computer to download images directly, it finds the magic lantern graphics and documentation files, and wants to download and delete them. I have to make a point of de-selecting those images each time if I want to keep ML nice and slick and self documenting.
I have seen this in Picasa, and using the windows built-in sd card handler for images. I imagine that any download program that searches the whole card instead of just the DCIM tree is going to have a similar issue.
I am proposing therefore that the images be given a non-standard filename extension so that the images are not identified as such by SD card download programs. The actual content of the files can be in what ever format they currently are, but the build system should rename the files as part of the deployment and the on-camera software should look for either file name, preferring the standard extension over the non-standard one -- that way developers who are tweaking the stored graphics do not need to rename their files for dropping them onto the SD card every iteration.