I can't remember seeing so many appeals to human authority as I have since the Study Editions of the Watchtower came out. Before the appeals of authority seemed to be geared more towards obedience to Jehovah and Jesus and the Bible. Now they seem very much geared toward obedience toward the "faithful slave", with some Bible scriptures to try to give credibility to their authority.
I also note a noticeable change in terminology over the past 10 years:
In the 80s and 90s, I remember hearing the phrase "The Society says" all the time. People have substituted this with "The Faithful Slave says".
While there is still quite a bit of "Jehovah has provided.." talk, there is more and more "The faithful slave has provided" going around.
I hear the use of "the Faithful Slave" a lot in comments and talks a lot more than I remember. Last meeting there were at least 3 mentions of the Faithful Slave in the Bible Highlight comments alone (which were based on the book of Job; Funny Jesus didn't get any mention).