There was 13. MWAHAHAHAHAHAAA. Take that Vexen! MWAHAHAHAAAA!
Anywho. Like I said 13. But we killed 5 of them. leaving 8. Two of which are Xaldin, and Demyx. Also the new female [She has been confirmed not Larxene] EM, which somehow wields a lightsaber. GEU. [Many speculate that it's Axel] The unknown sitting on the rock is DWU who is also BHK. The intentions of BHK is unclear. All that is known is that he wants to find Sora. If he wants to put everything back in balance the way it should be, then he's not a part of the Organization. But if he wants to remain an entity separate from Sora, then he is in the Organization. We saw him trying to attack DiZ. DiZ is trying to destroy the Organization. MY guess is that he doesn't want to become one with Ansem once more. So he intends to break up the group. There is definantly some connection between Axel, and DiZ. Only 2 people call DiZ, Ansem. That's Riku, and Axel. But back to the point:
1. Axel
2. Marluxia
3. Vexen
4. Larxene
5. Lexeaus
6. Zexion
7. Demyx
8. Xaldin
9. [The new female]
10. BHK [Possibly]
11. EM
12. GEU
13. Ansem
If that is the way it is,then it would all make sense. IF it is, I hope I didn't ruin the plot for myself.