The release notes for Enterprise 2014 mentions that 2015 will no longer support 32-bit Windows. the wording seems to indicate that it will only affect the "CAD Editor" license but will the viewer be affected as well? We have a couple of Windows 7 32bit users that use a viewer license.
This is something I wanted to know too. I have a lot of computers Still on 32 bit. I hope it only affects the Editor licence. Though I have some AutoCAD machines on 32-bit as well that will have to be down graded to contributor if this is true.