There was a thread about black in the main bowhunting forum where some people (including myself) were concerned with larger items that may stick out in the woods (my concern was how obvious a nylon strap's black horizontal stripe is on a light colored tree; I can spot those from hundreds of yards away and always break them up with gray primer paint on my personal stands.)

Having said that, I'm not worried in the least about accessories being black. They're too small to worry about, and often are no larger than many black shadows you'll see in the treetops normally.