The wikipedia article, Beliefs and theology of the Nation of Islam seems to have a lot of old information. According to the latest possible information, does "Nation of Islam" still hold black supremacist beliefs?
No-one would have heard of the Nation of Islam had Malcolm X not joined; after he joined its membership went up from 500 to 30,000. He was a hustler, a criminal and a pimp who became a spokesman for a generation, a fact acknowledged by Martin Luther King, who in this interview for Playboy in 1965 had to say this about the espousal of black nationalist and supremacist beliefs:
Many pent-up frustrations are boiling inside the Negro and he must release them. It is not a threat, but a fact of history that if an oppressed peoples pent-up emotions are not non-violently released, they will be violently released...for if his frustration and his despair is allowed to continue to pile up, millions of Negroes will seek solace and security in black nationalist ideologies, and this, inevitably, will lead to a frightening racial nightmare.
Malcolm X himself eventually broke with the NoI and turned towards orthodox Sunni Islam, this turn in his thought occurred after going on pilgrimage to Mecca, one of the incumbent duties of a practising Muslim. In his letter from Mecca he wrote:
Never have I witnessed such sincere hospitality and the overwhelming spirit of true brotherhood as is practised by people of all colors and races here in this ancient Holy Land, the home of Abraham, Muhammed and all the other prophets of the Holy Scriptures. For the past week I have been speechless and spellbound by the graciousness I see displayed around me by the people of all colors ... from blue-eyed blondes to black skinned Africans ... displaying a spirit of unity and brotherhood that my experiences in America had led me to believe never could exist between white and non-white ...
He goes on to write:
you maybe shocked by these words coming from me. But on this pilgrimage, what I have seen and experienced has forced me to rearrange much of my thought patterns previously held, and to toss aside some of my previous conclusions ... during the past eleven days here in the Muslim world, I have eaten from the same plate, drunk from the same glass, and slept on the same rug - while praying to the same God - with fellow Muslims, whose eyes were the bluest of blue, whose hair was the blondest of blonde and whose skin was the whitest of white. And in the words and the deeds of the white Muslim I have felt the same sincerity that I felt amongst the black African Muslims of Nigeria, Ghana and Sudan ... with racism plaguing America like a cancer, the so-called 'Christian' white American heart should be more receptive to a proven solution to such a destructive problem ... perhaps it could be in time to save America from imminent disaster - the same destruction brought upon Germany by racism that destroyed the Germans themselves ...
And he finds himself, despite his earlier indifference and irritation towards Martin Luther King, aligning himself with him:
the American Negro can never be blamed for his racial animosities - he is only reacting to four hundred years of the conscious racism of American whites. But as racism leads America up the suicide path, I do believe, from the experiences that I have had with them, that the whites of the younger generation, in the colleges and the universities, will see the hand-writing on the walls, and many of them will turn to the spiritual path of truth - the only way left to America to ward off the disaster that racism inevitably leads to.
This turn was followed by the Nation of Islam under the leadership of Warith Deen Mohammed, the son of Elijah Mohammed and the mentor of Malcolm X, the mentor that he frequently references in many of his early speeches and interviews.
In fact, Warith disbanded the Nation of Islam in 1976 and transformed it into an orthodox mainstream Sunni movement, the World Community of Al-Islam, which later became the American Society of Muslims. According to the Wall Street Journal, in 2002 their members were estimated to be:
near 2.5 million, with a percentage of immigrant and naturalised American citizens from various Muslim ethnic peoples, European Americans, and a majority of African Americans representing five generations since the earliest history of Elijahs Mohammed's leadership, and in some cases, before.
These reforms dismayed Louis Farrakhan and he eventually decided to rebuild the Nation of Islam on its former basis, using his own organisation, the Final Call as it's basis and regaining many of its former properties to legitimise it as the rightful heir of the original NoI; he has been described by the Southern Poverty Law Centre as both anti-Semitic and black Supremacist, and the newly resurrected NoI is categorised as a hate group.
Yes, it still does.
He is not calling explicitly for world-scale ethnic cleansing (either godly UFOs or the mahdi will take care of this), like what some alt-right organisations claim. But he considers white people to be black people bred by some "Mr Yakub" between -4600 and -4000 so that they turn evil. 200 years of evil artificial breeding lead to "brown people", 400 to "yellow people"; and 600 to "white people".*
About the members. I don't think a large number of followers joined the organisation without having these beliefs, it seems very unlikely. Mr Farrakhan has a web series on the official NOI website, and this story is due to the founders of the organisation. Besides, there are plenty of other associations in the US one can join, if one were tired of having this guy as a leader. But this last part is only speculative; a survey on the members is needed to confirm/infirm it.
*Having a story saying that other people are inferior is not that uncommon when it comes to religion. It is different than explicitly calling your followers to murder all of them, which is the approach taken by organisations like daesh. For instance, the mormons were openly white supremacists in the 50s, in the sense that their myths gave to black people a lower status. The mormon myths have been "updated" since.
No, but it does still have leaders who make anti Semitic remarks and given their recent history of black supremacist views they should be still be looked at skeptically under the likely scenario they are not publishing or speaking on certain beliefs to try to rebuild their image. Also the Southern Poverty Law Center, which tracks hate groups has them labeled as a black supremacist group, which matches their past rhetoric, and unless they specifically disavow their past views any new absence of their past views should also be suspect.