If swapping the boards don't work, that'll mean they've seriously modified the underlying hardware, so these DVD drives are a whole new beast. I'm betting they've either changed the pins (which will be easily fixed), or they've changed the hardware enough that the boards simply won't work (I reckon they would've gone for something like this).
If they've locked the drives to the Mobo like MS does to 360s (which I bet they have), then if someone is really desperate for a drive swap, there might be a way to emulate the drive in hardware to connect to another drive.
If anyone is going to do that, it'll be the WODE guys, and they'll add it as an extra feature to the new WODEs.