EHLO. Harald Welte at the OpenMoko project was kind enough to allocate the Rockbox project a block of 256 USB product IDs ranging from 1d50:5300 to 1d50:53ff.
Now that we have the PIDs, it's time to assign them to targets. The current plan is to allocate all the stable targets and some of the in-development ones (e.g. ipod6g) a unique PID, and all the rest a "generic rockbox device" PID. See http://www.rockbox.org/wiki/USBIDs for more information. Franklin