Did you know that black cats are the hardest to adopt out? There's mostly only anecdotal evidence to support this, but a lot of shelter workers say it's their experience. This 2008 Seattle Times article cites a 2002 study that supports the claim. Apparently some people just want more "exiting" or "exotic" looking cats, with stripes or spots. Or perhaps people are still made nervous by the old wives' tale about them being unlucky. Not only is that silly-- but it's rather an American superstition. Evidently in the UK and Asia black cats are lucky! A lot of US pet shelters won't adopt black cats out during October, for fear that they'll either be used as props for Halloween and returned, or that they'll be mistreated as part of pranks and rituals.
The only black cat fact that I can prove is that it's hard to photograph them!