The rejection is not due to the expiration date on the top corner.
If you look at the bottom right hand corner you'll see the revision date: (Rev. 05/27/08), and that's the only form accepted by USCIS right now. All previous forms that had the same expiration date but a previous revision date are boing rejected.
That would be my theory, too. They probably don't have much time to check all forms and some fall through the cracks just by glancing at the dates. Nevertheless lets hope they post an updated form soon.The only other option is USCIS making a mistake and randomly rejecting some of the new forms as well. Not much we can do about that though, unfortunately.