ColourOfSpring - 11:38 am on Jun 12, 2013 (gmt 0)
what does authority mean these days? it seems to be the sites that most people choose to use of their own back. For example a shopping search would see most users going to amazon. However is amazon an authority for the product? does it have the best information or unique content for the product? seems to me the meaning of authority has changed from in-depth product information to most likely to sell that product. In the old days the algo searched for authority based on informational parameters, these days it identifies authority based on user patterns.
Google's version of authority seems to equate to size - the bigger you are, the more authority you have. I'm sure people here will show counterexamples, and I know there are some that exist - but that's the general trend I see. If you're big, you're an authority. Pinterest is a great example of this. They're big and popular, therefore you see them ranking well for all kinds of keywords.