Sorry if this has been mentioned but....... In a famitsu article, I saw a picture of TAV sitting on an edge like ARX....
http://www.khinsider.com/images/BirthBySleep/famitsu_091210_01-02.jpg
Terra is sitting exactly like Axel. Since Terra is connected with Riku too, this might mean that Axel and Riku are connected too. Ven and Aqua don't look a lot like Xion and Roxas but terra does. I know this might be stupid.
http://www.khinsider.com/images/BirthBySleep/famitsu_091210_01-02.jpg
Terra is sitting exactly like Axel. Since Terra is connected with Riku too, this might mean that Axel and Riku are connected too. Ven and Aqua don't look a lot like Xion and Roxas but terra does. I know this might be stupid.