I've got one knocking about in the drawer. Let me know if you get beamforming working on it. I think there are multi channel audio drivers for Linux/RPi for PS3 Eye
Yes Kinect has an array of 4 mics and can do audio beam forming. Plus there's a terrific SDK for Windows.
I said it in a thread about the Kinect - I think it's only 135 (ish) degrees of reception, and sometimes it can be more finicky than that.