I'm putting drywall in a basement and I know the green side faces out but I'm not worried about moister from the inside of the basement. My worrie is the moister comming from the block walls behind the drywall so should the green face the block wall which i know would be backwards but thats where the dampness is going to come from.
Green board is not for use as a moisture barrier. If you have that much of a moisture isue you need to address that issue prior to installing your drywall so as to not allow the growth of mold behind the drywall in the stud/furring cavities. (I'm assuming you're not attaching directly to concrete which is a big NO!) That can mean either an appropriate moisture barrier or addressing the issue on the outside of the house where the problem begins (proper waterproofing, drainage,etc.). You never want to hang the drywall backwards. It makes the finishing twice the work as you eliminate the recessed edges and the backing paper is nowhere as smooth as the face paper, requiring "glaze coating" the entire surface to achieve a good finish. If your moisture issues are taken care of, there's no need to go to the extra expense of green board. Regular drywall will work fine.....
If you can read this, thank a teacher. If you can read this in English, thank a soldier. Support our troops.