Interesting comments in the Puget Sound Business Journal - this is sort of what Facebook did to application developers with notifications ... which is one of the reasons we're moving NewsCloud away from native canvas applications and moving towards using Facebook as just another authentication provider:
Before, when a user clicked the “like” or “recommend” buttons on a business’s page, anyone viewing that user’s news feed would see that the user likes that business or product. Same with comments posted to a business page. But Eckert says those aren't showing up in personal feeds anymore when clicked through Facebook, though they do appear in feeds when clicked through the businesses’ website.
“The ‘like’ button is being marginalized,” says Dave Ringler, Blind Acre’s director of marketing and product development. “How are businesses going to stay in front of their followers’ friends?”
It also means businesses will have to give more consideration to how they use “like” buttons on their websites.