Transferring files to and from the player via USB is the part that's not enabled yet; you have to use the OF for that. Charging works in Rockbox as long as you're already booted in Rockbox and you hold the Select (center wheel) button while connecting the charger. Otherwise it will auto-boot into the OF upon connection.
Another thing that has yet to be worked on is audio/line-out via the dock port...so no using speaker docks for the time being. I'm crossing my fingers for that inclusion, myself.
As for determining the difference between v1 and v1 Fuzes, yes, it's the same process as for the e200 series: You have to check the firmware on the player itself. A "V01..." designates v1 hardware, and a "V02..." designates v2 hardware.