Compile Heart is busy as a bee with the PlayStation 3. In addition to Record of Agarest War 2, they have another unannounced PS3 RPG.
Their GDC portfolio included a game called Neptune, which is currently in development. No details were announced since the game was only seen on a list.
On second thought, “Compile Heart” may not be responsible for Neptune. Compile Heart is basically part of Idea Factory and their list included a number Idea Factory titles such as Trinity Universe and Hakuoki. Either way, some branch on the Idea Factory tree is developing Neptune.