No one knows other than the people who work for Google. Nowadays many new things are implemented in Google daily to attract people in a greater way. Almost 70 percent of the people comes only to Google rather than yahoo and bing.
What i think, still matt cutts may not sure when google updating any algorithm
Only we can implement the things when we are getting any success then we can say, yes it was
By the many experts/gurus many views, which one we can say the point??
THere are many great blogs you can follow to help you keep track of googles updates. Google even has their own blog that they use to give information.
Just google: google blog.