dont worry im 100% sure you have nothing to worry about.
Only profits and maniacs claim to have 100% knowledge of the future---which one are you? On the other hand, worry never a good thing (IMO).
Nevertheless, I agree that most-likely there will be nothing to be done from the perspective of a multibit-user. MB is developed by Mike Hearn (IIRC) and he's one of the proponents of the increased block size (again, IIRC).