Essay and/or background: In an essay published in the New York Times on May 20, Mark Helprin argued that copyright should last forever. He equated intellectual property with physical property. In response the piece, several people over at The Lessig Wiki put together a page refuting the thesis. Here, I've attempted to capture those arguments and hopefully people can build off it. It might also serve as a nicely organized reference for showing people who aren't familiar with the debate a new perspective.
Cruxes...
The top point in support right now is, "Time-limiting rights of copyright owners is morally equivalent to doing that to owners of physical property."
The top counterargument is, "Copyright should only last long enough to provide incentive for creation, since the ultimate purpose is to benefit society be enriching culture."