It's true that the Niger delta agitated for a country of its own , which was lead by Isaac Boro,  but it failed to come to existence. Then the Civil War which was for the creation of Biafra which also failed. I am really not concerned about the country splitting,  because I still feel that its still the same politician that will  continue to rule and either Biafra or Nigeria will still remain the same, until the citizens and the government decide to take a stand and make the country a better place.
I also believe that the reason the Niger delta do not support Biafra is the feeling that they will be minority group while the south east will be the majority,  so it still the same old story for the Niger deltas.