The Sega CD is actually supported by the SG. The little foam spacer that comes bundled in raises it enough to snap into place. It looks kinda goofy, due to how small the SG is, but I've heard the results are amazing.
Even 32X might be happening eventually.
Oh no, I knew that! I have the SG myself. What I was wondering was if the jailbreak also includes playing Mega CD ISO's from SD card. That would be something pretty cool.