According to Scotusblog:
The Bilski patent case that the Court agreed to hear will give the Justices the option of defining the scope of patent law to take account of the impact of the digital age on developing software that controls human activity, such as making business decisions about how to scope with economic risk. The U.S. Solicitor General had urged the Court to bypass the case, but the Justices did not take that advice. The case has generated hot, and even worldwide, controversy since two inventors in 1997 filed an application for a patent.This is the first time since 1981 that the Supreme Court will rule on the scope of patent protection.