/sbin/init is a nonstandard init for a good reason: boot time & other bits & pieces. Basically, we needed a small init which would (a) mount the music parititons and (b) run the player. It also (c) restarts the player if it falls over (hopefully unlikely ;) ) and ensures the system is in a safe state after fallover (ie, ensures the disks are read-only in case the player fell over during a music download).
We may make the source to our init available - though almost any custom add would probably have different criteria on what was best to do and so would just run their own init script.
hugo