I think there was a method to convert from one to the other posted on here, but it was not easy -- at least, I didn't find it to be.
Ted, what about whipping up something that uses AppleScript for the Mac-folk among us, and WindowsScript for the Windows-folk? Wine would probably support it for the Linux folk.
Ideally, the program would allow the user to drag-and-drop their .json file on to the program's icon and it will do it's thing, saving the file to the same directory the original was in -- and not change the original.
--gdw