Actually there was at least one change to the SP game. Many people had complained that it was not possible to get your build version to 10.0.0. Due to this complaint, they patched this in the latest update.
Apparently the saved game incomparability is not a problem if you were running 1.04, but I'm not 100% sure on that one.
For the latest Tron 2.0 info check out:http://tronforum.boxhat.com