Too Human was announced as a trilogy when announcing games as trilogies before the original was a proven success was en vogue. When the oft-delayed Too Human was released to mixed reception and sales and developer Silicon Knights legally went after Epic Games over the development of Unreal Engine 3 (a suit that's still ongoing), the future of Too Human's unproduced sequels was left sitting in doubt. 

Two Silicon Knights employees made comments about the future of Too Human today, oddly enough.

"We intend to finish the trilogy but no comment beyond that," said company president Denis Dyack in a comment to Industry Gamers. "You know, there's very public litigation around that."
Separately, assistant project director Julian Spillane introduced himself to the "official" Silicon Knights community (the spin-off is actually endorsed by the studio on its own website) and addressed the issue.

"Well, unfortunately we can’t talk about any of the unannounced games we’re currently working on," said Spillane, "but we can definitively say that we do plan on finishing the trilogy. "

There's a stark difference between intention and bonafide development, however. 

Silicon Knights is currently developing the RPG-focused X-Men: Destiny for Activision.