Living Proof
Member
The E3 demo had pretty clear "Save Game" "Load Game" options in the menu, which I assume are save-states.
While some form of save states have been confirmed, be careful not to make assumptions off of things like this. It's plausible that the save/load screen simply replaces the old password system necessitated by the lack of battery backup in the original cartridges.
Of course, seeing as the developer wants a purely authentic experience, this could very well be incorrect too-- just thinking about the technical constraints they're willing to work around compared to the authenticity they strive to preserve (however disagreeable that may seem).