Looks like the cover art has been released!
http://www.jp.playstation.com/scej/t...ja/soundtrack/
Also, I asked Mr. Mitsuda on Facebook if he composed more than the main theme. He said that he and Mr. Hokoyama each composed half of the score.
Here are his exact words:
PS3のゲーム「アフリカ」の音楽を手掛けた鋒山亘さんと半分ずつぐらい作曲しています。
鉾山さんの楽曲もめちゃめちゃカッコイイので是非お楽しみに！
Also, here's a live video of the orchestra playing Mitsuda's main theme at Skywalker Sound! Link to the official site:
http://www.jp.playstation.com/scej/t...d/mitsuda.html