Interesting timing for this. Alexandre has been updating the linux-libre kernel regularily for a couple years or so, matching every upstream (& -stable, -rc) release.
On the LKML side, David Woodhouse has been plugging away moving firmware out of "random" locations in the kernel into a firmware/ subdirectory and using a common method for the firmware to be loaded (instead of each driver making up its own way). As I understand it, this whole firmware/ directory is likely moving out around 2.6.38, so all the non-free binary blobs that are currently in the kernel will be gone. Well, gone to a file outside of linux-2.6.xx.tar. RSN, the Linus tree will be free of non-free software. :)