Her's the source
With God of War 3 having released back on early 2010, it’s a safe bet that Sony Santa Monica are quite far along with the development of their next game. No one is really sure what the studio is working on, with many speculating that they are developing a new GOW, perhaps set in a different mythological setting. However, a recent job listing now confirms that they are working on a new IP, although no platforms are specified.
Over on Gamasutra, the job listing states:
The Sony Santa Monica Studio is hiring for an unannounced new IP!Additionally, the advertisement reveals that “Experience in designing or contributing to the development of an “open world” game is a plus.” This backs up previous job listings that looked for experience in open world games, as well as vehicular combat and shooting games.
I'd rather it be something more fantasy based with a heavy focus on story and atmosphere. Something like Okami. Not neccesarily gameplay wise, but in terms of how the world and art service the story elements.