Copyright should last 5-10 tops. In the current digital world it is more than enough for monetization and we don't lack creation of artifacts which copyright was created to spur. So we may tone it down a bit.
Should JK Rowling not have been receiving money from the first Harry Potter book (published in '97) for the last 6-11 years? Sure she's rich enough already... but why should she lose out on that money which she arguably earned?
And not everyone gets rich in the first few years after publication. My mother is an author of children's books, and my grandfather was a composer - money still comes in (not to me, to my mother and her sister) now, many years after some work was written, but it's never been a huge amount, even at time of publication, yet alone now.
I'm personally a fan of the (life + X) model, whereby it extends a little beyond the creator's death. I don't know what that X should be, though I do feel that the X=70years that we currently have in the UK is too long. But while the creator is alive, why should they not continue to earn money on their work?
She can continue to earn money by making a competitive product. A copyright is a short-term monopoly granted to ensure that authors can recoup expense before the rush comes in. It's not meant as anything more than that. Whatever she makes in the first five years since publication is all she "earns" simply by holding a copyright. The rest of her money must be earned by contributing further to the progress of science and useful arts (perhaps by writing a sequel, which would have its own copyright term...) and/or competing on the open market with everyone else.
If the public takes the time to integrate your story into its culture, if they read your book and pore over the characters and develop their own interpretations and feelings, they should be able to share these commercially within a reasonable timeframe. When you publish something, it's not your own anymore.
I think Joss Whedon had a cool quote from a reddit AMA a while back. It was something like "Art is not a pet that you keep forever, which follows you around loyally without criticism until the end of its days. Art is a child, and it grows up and moves out and talks back to you." The real quote is probably better, but that was the concept.
This is one view, but to say that "it's not meant as anything more than that" is not accurate. Even John Locke believed that authors had fundamental rights to their creation. (source: http://papers.ssrn.com/sol3/papers.cfm?abstract_id=1983614)
The Continental Congress resolution to pass copyright legislation was inspired by author Joel Barlow who wrote in his 1783 letter to Congress:
"There is certainly no kind of property, in the nature of things, so much his own, as the works which a person originates from his own creative imagination: And when he has spent great part of his life in study, wasted his time, his fortune & perhaps his health in improving his knowledge & correcting his taste, it is a principle of natural justice that he should be entitled to the profits arising from the sale of his works as a compensation for his labor in producing them, & his risque of reputation in offering them to the Public."
The problem is that we are moving in winner takes all IP economy. So the copyright that made sense a 100 years ago just doesn't fit our fast moving world. The winner takes all now and will take a lot in the future. In the current world visibility is the problem not the copyright.
Also we are able to lose works this way - which is scary. Even if 95% of everything that is crap it is still worth preserving. Right now NOLF - one of the best games ever is in limbo - no one knows who owns the damn rights.
But I do feel that for works from single author it makes sense to be lifetime. But not for corporate ones.
In 10 years you won't have the hardware to run the game you will hold the rights to for the next century. It is absurd.
Other people could take everything you own and created 5-10 years ago. If you have a regular 9-5 job at a big corporation you might not care but for content creators who make content once, then collect payments years down the line (Music/VideoGames/Films/Authors) that would devastate them.
And most stuff with 200M production costs either flops and never makes it to black or makes the money back in the first month or so. Otherwise waterworld would be considered a great success.
Copyright should be incentive to create and not rent seeking.
This isn't a big deal to limit the copyright on.
So Disney gets to keep Mickey so long as they keep using Mickey, JK Rowling keeps Harry Potter so long as she's still writing books and keeping the world up, and the same with Star Wars. However, if nothing new comes out between extensions it falls into public domain. That would catch all the books, 1 hit wonders, orphaned video games (heh, maybe Half Life would be public domain with the wait for HL3), etc.
Not a fully fleshed out idea (What about after death, if your kids kept up your bestselling X, or if you released a 10th edition of your horrible book with "THE END" added), but it's an idea.
This small change wouldn't impact the big corporations, but it would start letting smaller things fall into public domain. Then, after a while of acceptance, you do something like limit the number of renewals, make it price prohibitive to renew more than 2-3 times, or limit transferability.
Or you could go for a big bang change and hope you have a critical mass of votes.