I <3 this idea!
As others have stated, Jap release has come and gone already so chances of us seeing anything is nill. =/

They should have done something though damn it! FFX is (imho and many others I would dare say) WAY more popular with the FF fan base than the XIII fiasco. Speaking of XIII, they DID fan service for that release as others (Myahele think posted it first) pointed out. So SE has shown its intention for such tie-ins and there are numerous other instances already in-game of various FF game nods.