U.S. copyright terms have increased several times in the last century, and are valid for up to 70 years now (thanks to the mouse). Most copyright owners are unknown, the copyrights those unknown owners own can’t be bought or sold or even put into the public domain for general use. There’s not even a good registry of who used to own each copyright.
Cemetery plots are owned for an indefinite amount of time, many of the owners are dead, and often its not clear whether there are any living next of kin. So if you see an empty plot in a cemetery, you may not be able to buy it, even if nobody has used it for many years. Nor can the cemetery owner or operator turn the plot into a park or otherwise repurpose it for general use.
Dr. Lessig didn’t say much about this analogy, but at least he didn’t say it was bogus.
In any case, it seems there must be a better system for protecting authors’ rights and promoting creativity and the economy.
-jsq