So if Google is a parasite, "stealing" their content, why not simply opt out of being indexed by Google? They could do it this afternoon if they wished.
Simply withdrawing from Google or erecting a higher pay wall would hurt News Corp. more than it would hurt Google. The Wall Street Journal's site was re-engineered early in Murdoch's tenure to make more WSJ Online articles free and summaries of the rest searchable, while maintaining the site's lucrative online paid subscriber base. Some call it having your cake and eating it too.
But a broad movement of branded news sites to a preferred relationship with Bing would not be so easy to shrug off. Microsoft could become an important player in the paid content equation. Google might counterbid to prevent that from happening.