I asked this before, but learned the answer was erroneous. This was the best answer I found:
zeldalullaby021 posted. Just an update, here's a response I got straight from Activision asking them which portals were compatible with which systems:
Hello, Thank you for contacting Activision Customer Support.
Yes but they are not all compatible. The Xbox portal will only work on an Xbox. The 3DS portal is universal and will work on any system except an Xbox. The PS3 and Wii have the same portal and will be interchangeable and can also work in the PC version of the game. The PC portal will only work on the PC version of the game. All portals will work for the Web world.
Please feel free to contact us again for technical issues or questions Have a Happy Holidays!
So according to them, there are NO portals, including the 3DS one, that will work on an xbox, aside from the xb360 portal itself. I might just bundle up everything & see if I can swap the wii version for the xb360 one somewhere.