Of course that's a "should" not a definitive. Historically Apple usually only changes firmware and/or EFI (bootable) support if they release a hardware refresh, which is something they not-coincidentally often do with the release of a new OS. (Maybe the Sept 9 "Apple event" will coincide with a minor hw refresh?) However, that doesn't mean this time around they won't cripple the firmware and/or EFI of new boxes that roll off the assembly lines to limit Leopard support immediately. It's just an educated guess that they won't go out of their way to do that.
