What these guys said.
You might think, as a creator of intellectual content, that I'm in favor of having my copyright last until the Sun is a cold darker cinder. I'm not. There are real costs to us as a Society to keeping content out of the public domain for too long. The free availability of public domain works created when copyright law was more sane is a great boon to me. I love Google Books
Here's my modest proposal. Continue to accept the terms of the Berne Convention, but require individuals to renew every thirty years after original publication to maintain their rights. And allow corporations to do the same, but charge them a fee large enough that they only renew works that still have significant economic value to them. Disney can afford it.