So, looks like someone else is experimenting with an alternative color filter array. Specifically, RC,CB 2x2 array. C being clear, so having no filter over it instead of a green filter, while still having R and B with standard filters.
http://www.anandtech.com/show/7149/aptina-announces-ar1331cp-13-mp-cmos-with-clarity-plus-we-take-a-look
http://www.anandtech.com/show/7149/aptina-announces-ar1331cp-13-mp-cmos-with-clarity-plus-we-take-a-look