>>The Supreme Court has been very reluctant to create categorical rules in terms of patentability<<
I wouldn't say very reluctant. There were four votes for a rule putting software and business methods outside patentability in Diehr (450 U.S. 175 (1981)) and again in Bilsky (561 U.S. ? (2010)). If Obama gets a chance to replace one of the pro-software patent justices (Roberts, Alito, Kennedy, Thomas, Scalia), the result could be different next time.
Note that in both those cases, the justices that were skeptical of software patents were those typically classified as the "left"-wing justices. I have no idea why that happens. Dr. Lessig had a theory in Eldred v. Ashcroft that he could win over "right"-wing justices for textual literalist copyright reform but it was only the "left" justices that finally agreed with reason in that case; even then it was only the most avid patent reformers he won over: Stevens and Breyer.
I wouldn't say very reluctant. There were four votes for a rule putting software and business methods outside patentability in Diehr (450 U.S. 175 (1981)) and again in Bilsky (561 U.S. ? (2010)). If Obama gets a chance to replace one of the pro-software patent justices (Roberts, Alito, Kennedy, Thomas, Scalia), the result could be different next time.
Note that in both those cases, the justices that were skeptical of software patents were those typically classified as the "left"-wing justices. I have no idea why that happens. Dr. Lessig had a theory in Eldred v. Ashcroft that he could win over "right"-wing justices for textual literalist copyright reform but it was only the "left" justices that finally agreed with reason in that case; even then it was only the most avid patent reformers he won over: Stevens and Breyer.