…in Monday’s ruling, Souter said lower courts could find the file-sharing services responsible by examining factors such as how companies marketed the product or whether they took easily available steps to reduce infringing uses. "There is substantial evidence in MGM’s favor on all elements of inducement," Souter wrote.
This legal analysis suggests the Court in fact upheld the Sony doctrine. Matt Yglesias makes some good points, see David Post as well. Here is a good argument that the ruling places a big tax on the marketing departments of technology companies.