They have.

As always, the question becomes: who watches the watchmen?

What independent oversight exists to ensure this leading source of news for so many around the world is actually operating impartially, without any subtle bias designed to "nudge" the public in a certain direction? I hope google handles this well, but certain aspects open the door to shenanigans.

This information won’t be available for every search result

• What if google executives or a program manager disagrees with a "fact check"?
  
• Will that fact check be punished in their results? Will their information not appear? Will that "fact checker" be banned entirely?
  

These fact checks are not Google’s

• Increasing the importance of monitoring their "fact check" sources to ensure the "fact checkers" themselves remain objective.
  
• Is it even possible to lose "fact checker" status after it is granted?
• What is google's plan for this? What happens if / when one of the "fact checkers" starts slipping in quality and objectivity? Or starts demonstrating bias as their organization changes?
  
• How would google determine that, fairly?
  

As we make fact checks more visible in Search results

• At the expense of other mainstream news stories? Will they be pushed further down the page to highlight and create space for the fact checks?
  
• It appears "fake news" still appear in Google's results?
  
• Why develop a system that "approves" only a narrow band of news or "official" story, rather than developing a system that better "filters out" the fake news and leaves all reputable news providers intact?
  
• Does this program seek to become an arbiter of truth rather than a conduit of information?
  
• Won't this force media outlets to cater to the "approved fact checkers" before all else?
  

I'd feel more comfortable if there were some sort of broader, aggregate rating factor rather than just a few "official" or "approved" arbiters of truthiness.

I respectfully believe that the best way to combat "fake news" is not by telling people "yes" or "no", but by exposing them to a variety of perspectives from reputable sources and allowing people to see a broader picture beyond simply seeing the "officially endorsed" picture of things.

Show me the coverage of an issue from NBC, ABC, CBS, Washington Post, New York Times, Wall Street Journal, highly regarded and non-partisan think tanks, government reports, prominent and reputable blogs, etc. Let me see their reports, understand their different data, and be exposed to the various bits and pieces some report but not others, so that I may see the full picture and understand the issue as near to the "truth" as possible.

Do not narrow my selections, tell me what to think, or prioritize certain officially approved arbiters of truth at the expense of other equally reputable sources of knowledge.

tl; dr: Do not help us see the truth by showing it to us through a straw - by narrowing our choices and selecting those who may serve as arbiters of what is 'true' and 'false'. Help us see the truth by showing it to us through our own two eyes with our full field of vision - by providing us a broad range of reputable sources and allowing us to see the ways they overlap and complement each other in painting a picture as near the "truth" as possible.

Don't narrow our vision or provide us the 'endorsed' or 'officially approved' take on things. Give us competing perspectives from reputable sources, and trust that we will be able to figure it out from the CBS/ABC/NBC/Times/Post/Journal/etc.'s combined efforts.

Don't tell me the 'truth' or knowledge you endorse. Just give me access to knowledge - and trust in human beings to learn from that knowledge; grow from that access (including our mistakes); and evolve freely in our thinking and personal beliefs on all issues.