Entering dodgy ground here but here goes....
I thought black was both a good heat absorber and emmitter.
White is a heat reflector. It neither absorbs or emmits heat as efficiently as black.
Concorde is painted white to reduce heat buildup. It must be fairly critical because when the BA fleet was repainted in that Grey and blue scheme they couldn't do concorde that colour (perhaps Bellepheron can confirm this). But as I write I am reminded they painted an airfrance concorde in Pepsi colours (blue). Did it fly??
Coincidentally gliders are painted white because it reduces the breakdown of the gel coat by the sun. They reckon if they painted them black they would degrade quicker. Wing tips usually have red flashes on them to make them easier to spot but they are limited in how much they can apply.
As for conspicuity black does seem to work well. You can see the hawks much more clearly both against sky and ground. Its ironic the RAF have taken that long having gone through all of the raspberry ripple, blue/yellow, silver/yellow colour schemes to come up with black. The only catch is the plane gets incredibly hot after standing in the sun.
Hope this helps.