ISPs and Secondary Liability

I was re-reading Perfect 10 v Google last night (and Perfect 10 v Visa) in preparaton for a cyberlaw class today and I was struck (again) by the 9th Circuit’s desire to maintain a clear distinction between contributory and vicarious liability in the ISP context.  While noting that the lines between contributory and vicarious liability are not clearly drawn (quoting from Sony), the court wanted to ensure that the lines were not further blurred by overly zealous application of vicarious liability to Google’s activities in in-line linking to Perfect 10’s copyrighted images.  I’m wondering if the policy behind these comments is really to ensure that more ISP cases are decided under contributory liability where the focus is more on the state of mind of the defendant than under vicarious liability which is a strict liability issue.  Perhaps the court wanted to encourage later courts to clarify the scope of the contributory liability test post-Grokster.  Or maybe questions about when Internet intermediaries should be liable for the conduct of others are becoming so complex that the court wanted to encourage future courts to focus more on the intermediaries’ state of mind than on other more ‘objective’ factors.  I could be way off base here about all of this and the case might just be a standard application of direct and secondary liability doctrines, but I did seem to read in a concern that courts focus more on the intermediaries’ intentions than on the more objective criterion of direct financial benefit and ability to monitor and control the primary infringer’s conduct.