This case was about jurisdiction of serious criminal cases and will have no change on land ownership.
However,it is likely that an Indian Defendant accused of a crime in another tribes "reservation" and charged in a State Court will likely asked for the case to be transfered to a Federal (or Tribal) Court. If that motion is denied, then it is likely that an appeal to a Federal Court, citing this decision, will ensue.The opinion is fairly narrow:
It applies to the Creek Nation.
It applies to Indian defendants who are accused of committing a crime under the Major Crimes Act in the Creek Nation.
That is all.