Jesus was not clear about the identity of the faithful and discreet slave.  Over the years, the term was used by Jehovah's Witnesses to refer to Christian ministers, Pastor Russell, and the 'anointed remnant' of the 144,000 spiritual Israelites with the heavenly hope. In recent years, there has been a shift in thinking. Even though most Jehovah's Witnesses are unclear about where their 'spiritual food' comes from, it is generally thought that the Governing Body of Jehovah's Witnesses is in charge of doctrines and that they represent the anointed remnant, also referred to as 'the anointed class'. 
For decades Jehovah's Witnesses believed that the Governing Body received direction from the 'anointed' remnant. They believed that the 'anointed remnant' was the faithful and discreet slave and that the Governing Body was the spokesperson for this elite group. However since the early 1980's, reliable sources have suggested that the anointed remnant has no impact on the doctrines or teachings of Jehovah's Witnesses. The organization is run by a few men who call themselves the Governing Body.
Finally in 2009 the Watchtower came out admitted the truth. They said this. 'a limited number of anointed men have the responsibility of representing the slave class. They make up the Governing Body of Jehovah’s Witnesses. ... Whether we are “domestics,” who are part of the anointed remnant, or we are members of the great crowd, let it be our determination to cooperate fully with the faithful steward and its Governing Body.' Watchtower June 15, 2009, Article: 'The Faithful Steward and Its Governing Body.'
According to the June 15, 2009 Watchtower, 'Christians who have truly received this anointing do not demand special attention. They do not believe that their being of the anointed gives them special insights beyond what even some experienced members of the “great crowd” may have. (Rev. 7:9) They do not believe that they necessarily have more holy spirit than their companions of the “other sheep” have.' 
As Jehovah's Witnesses we used to believe that God's 'faithful slave' and anointed members of the Governing Body must be obeyed because they are in a 'new covenant' with Jesus and the rest of us who belong to the 'great crowd' are not. The only way we can benefit from the sacrifice of Jesus and be saved is to remain united with the anointed remnant and follow their guidance.
Now we are being told that the 144000 anointed spiritual Israelites have no special insights and that they don't have more holy spirit than the 'other sheep' or 'great crowd'.
Why is yesterday's truth changing? We do not know for sure. However there is speculation. See Governing Body
The truth of the matter is that the anointed 144,000 Jehovah's Witnesses who claimed to be spiritual Israelites were never more special in God's eyes. There was never a good reason to follow ordinary men. Yesterday's 'truth' was never true.
The Bible says, 'there is one God and one mediator between God and men, the man Christ Jesus, who gave himself as a ransom for all men' 1 Timothy 2:5,6  ALL Christians have a direct relationship with God symbolized by baptism
Since the Watchtower says that anointed Christians don't have 'special insights' and the Governing Body has been comprised of anointed men for many years, it's obvious that neither the faithful and discreet slave nor the Governing have any special insights either.
Apparently the opinions of all experienced Jehovah's Witnesses are now just as valid. Since we are now equals, Jehovah's Witnesses would do well to worship God directly based on their own conscience.
The Governing Body is typically comprised of 8 - 12 +- male only Jehovah's Witnesses who run the organization and decide on church doctrines. Praise God. Jehovah's light is getting brighter and brighter.
1. The identity of the faithful and discreet slave is not disclosed in the Bible. It is not clear if the 'slave' is a person, a group of people, or a symbolic way illustrate something else. Matthew 24:42-51
2. "The Faithful Steward and Its Governing Body", The Watchtower, June 15, 2009, pages 23, 24. Watchtower July 15, 2010 pages 22, 23; Franz, Raymond, In Search of Christian Freedom. Commentary Press, 2007, page 153. ISBN 0-914675-17-6.
3. Jehovah's Witnesses believe that Jesus is not the mediator between God and man like the Bible says in 1 Timothy 2:5. They believe that Jesus is the mediator between God and 144,000 spiritual Israelites. The only way for other Christians to benefit from the sacrifice of Jesus and receive eternal life is to obey these anointed ones. According to Jehovah's Witnesses, only the 144000 have a direct relationship with Jesus. The rest of us need to have a good relationship with the 144,000 in order to be saved. Who are the 144,000? See Governing Body
The Bible says that Christians have direct relationship with Jesus symbolized by baptism. Jehovah's Witnesses believe they don't have a direct relationship with Jesus unless they are part of the 144,000. See What Jehovah's Witnesses Believe About Jesus
Read more about the Jehovah's Witnesses Organization
Also consider: Theocratic Warfare ( withholding the truth from those who don't need to know ) Are Jehovah's Witnesses entitled to know the truth about the faithful and discreet slave?
JW's are told they must obey God's 'faithful and discreet slave'. What is the truth?