I think it is safe to say that the countdown has begun — the countdown to it becoming more difficult for you to leave Japan with your children. Difficult, that is, if you are non-Japanese and traveling without their other parent (or his or her written consent).
The recent arrest of Christopher Savoie in Fukuoka for trying to "abduct" his children back to the United States (or into the U.S. consulate, at least) has highlighted what is being characterized in the Japanese media as a new and growing problem: foreigners abducting their children back to their home countries. If they aren't forcibly grabbing the kids like Mr. Savoie, they are taking them back home for a "visit" and then never coming back.
These are often children who were born and raised in Japan, yet their fates are being decided in foreign courts where the Japanese parents are often handicapped by distance, language and expense. If this sounds familiar, it is because it is just a reversal of the experience of scores of foreign parents whose children have been unilaterally brought to abduction-friendly Japan.