If I look down on that page, I noticed that Peace Walker will have a Drama CD as what Hideo Kojima announced earlier that month. It's not just a Drama CD, they'll also have two character songs included, plus BGMs never before released in the Original Soundtrack.
Two character songs will be led by Akio Otsuka (as Snake) and Tomokazu Sugita (as Kazuhira "Kaz" Miller), so if you guys haven't heard of it, this will come out on this CD this fall.
Akio Otsuka, as Snake, will sing "Showa Blues" and Tomokazu Sugita, as Miller, will sing "Minato no Yoko Yokohama Yokosuka", making fans more interesting.
Hope I can pre-order that CD...