I just finished this bottle on the weekend.  Considering its size (1.14L) I think I made rather short work of it.

According to the Bacardi website, BACARDI® Black is aged upwards of four years to create a medium full-bodied blend with aromatic impressions of tropical fruits, apricots, plums and banana. It has a continuous woody finish with hints of vanilla.
 
I agree with that.  It is definitely on the sweeter side, and I would say that it does have a nice fruity quality to it, not so much vanilla.  I generally mixed it with coke, but I think it is smooth enough to be consumed straight.

I am guessing they called it Black because it is a very dark colour.  I used to associate the colour of rum with its strength (darker being stronger tasting) but that is often not the case.  The Kraken is another example of a dark rum isn't particularly strong. 

I wouldn't hesitate to buy this one again, but not right now as I think I have more than enough bottles to work on.