A recent Wall Street Journal article highlighted the importance of reviewing estate planning documents after a divorce. The article referenced litigation pending in New York where a woman named her father-in-law a beneficiary in her Will. The Will was executed prior to the divorce.
New York has a law (as does New Jersey) providing that upon divorce, the ex-spouses no longer have an interest in each other's estate. That rule applies even if the ex-spouses do not get around to changing their Wills that were executed while they were still married. The issue in the referenced litigation arose because while the New York law applies to the deceased woman's ex-husband and disinherits him from her estate, the law does not expressly apply to her ex-father-in-law.
In addition to possible testamentary gifts to an ex-spouse's family, there are other potential issues such that it is a good idea to review estate planning following a divorce. The Wall Street Journal article is available here.