YES:
 * Specifying rootfs location filesystem type
 * Start different init than /sbin/init
 * Configuration examples, HOWTOs
 * DNS configuration.

MAYBE:
 * Change the rootfs_part= argument handling, so that it would accept arbitrary
    ammount of transformations; will lead to awesome stuff like transforming
    next parts using scripts downloaded in previous parts.
 * Compression algorithm autodetection based on filename OR bsdtar automagic
 * Fancier OK/FAIL - at the end of the line, or somewhere

DONE:
 * Downloading rootfs over http
 * Other compression algorithms
 * Rootfs "overlays"/"parts"