Google Shopping has announced a new suite of bidding strategies for Shopping campaigns. According to google, these will enable maximum clicks, an enhanced CPC for self-management of campaigns, and an automated bid system to target ROAS (return on ad spend), although you should note that this last one is in Beta.

These enable you to go beyond manual max CPC bidding to deliver specific bids for each auction, tailored to people’s context. Google Shopping: New Suite of Bidding Strategies [adwords.blogspot.com]