The terrain patents expired, but they
did renew the Heroscape trademark:
So although Hasbro could reprint Heroscape sets or come up with new sets, ANYONE can make compatible terrain. However Megablox and others make Lego compatible bricks, but that doesn't stop Lego from being the leader in bricks and minifigs, so still incentive for Hasbro to make, and they still have the molds as well.
I think there is a demand for it, but rather than Haslab making it, I would rather see Restoration Games (Rob Daviau), Soaring Rhino (Craig Van Ness), and/or PlaidHat (Truth/Colby Dauch) make a "Heroscape 2.0" even without the Heroscape trademark but using Heroscape terrain, as they will pay more attention to the game and make it better than Hasbro would as just a cash grab.