What I think should be reasonable is a "creator's bill of rights." One that incorporates the same "use it or lose it" language as book contracts.
In a book contract, the publisher is obligated to keep the book in print. If the publisher does not do so in some form, in X years (varies by publisher, author, and how aggressive the author's agent it), the rights go back to the author to be resold or redistributed as the author sees fit. The only one of my books to ever go out of print has recently reverted, and the Marion Zimmer Bradley Trust is putting it back in print in e-format.
This would prevent firms like NCSoft from squatting forever on an IP, which I think is only fair. Given how fast things move in the game industry, I think a 1 or 2 year limit on IP squatting is reasonable. This would also give firms the incentive to sell while they still can.