Ambient background bias lighting - does it make a difference?

[Maki]

I am in the UK and have a Pioneer 507XD the last before the Kuro's. It does not have the best blacks in the world in a dark environment, however with a back light, an uplighter in my case the blacks become much better.
In any case watching in complete darkness is not always the best idea. All Plasma's blacks glow a little in total darkness, maybe Kuro's are an exception.