DNA studies move ahead on all fronts. No doubt there will be a definitive answer in the long run.
There's been a cottage industry in "black studies" over the question of whether or not the Greek's had African ancestry of course, but that's not quite what is driving this particular issue.
Mummies are available for analysis and as Ptolamy family members are identified, the question of Cleopatra's ancestry can be dealt with.
A black friend of mine got interested in the whole "Black Egyptian" thing about ten years back and actually went on a tour with the leading theorist, Dr. Yosef A.A. Ben-jochannan. They were shown all the evidence and my friend quickly came to the conclusion that it was all BS. Part of the theory is that the reason the noses were broken off the statues was to cover up that they were black noses, but when my friend pointed out that even the later Roman period statues of Romans also had their noses broken off, the guy just kinda shrugged.
He said the funniest part of the trip though was walking through the bazaars. The peddlers there would call out "American Nubian! American Nubian!" He realized he was just another sucker.