Well, the current progress I'm seeing doesn't pass my build chain (compared to other platforms), as several maps and defines and #ifdefs are missing; but nothing catastrophic there. Judging from what I'm seeing there it doesn't feel like there really was a firmware at hand; and I'd love to be able to have a look at the objdump myself, and see how I can help.
Knowing other firmwares would of course help finding commonalities to identify entry points, but I know my C and my Linux and have a camera at hand, so I'm definitely willing to try ... considering that the 70D is showing "hello world" & more is giving me a certain amount of hope in either case. Guess I'll have to look for the code for that, too; it's not in the main repo (yet).
Any specific person to talk to on IRC, anyway? I'm "count" on Freenode.
Cheers,
count