Well, that was disappointing, the scythe could have been a clue for Grim Fandango...
Anyways, here's some more tweets:
"As original ND projects progress, previews will happen. Rereleases though, it is out of our hands. We do the work to get classics back out."
"The point being, we'd love to just tell you what we're working on re-releasing! But we can't
So, it seems like they're still working on something else, but it might be a while before we find out what that is.