As you may know, Google has a group of people called quality raters, who evaluate the quality of sets of search results. Here's a video of Matt Cutts discussing how Google uses these people:
And here he is talking about them more:
Last year, Google posted what it called the "CliffsNotes" version of the Search Quality Rating Guidelines document for all to see.
The actual document has been leaked a few times in the past (it's continuously updated), and now what appears to be the latest version has made its way to the public eye. Jennifer Slegg picks them apart here (via Search Engine Land)
Here's the full guidelines document:
Unsurprisingly, Google is still looking for authoritative content. The date on the document is March 31, 2014.
At least this will give you something to look at while Matt Cutts is away from his job.