It is a pretty subtle difference Peggy, I have noticed a huge difference in colours between my desktop PC with big monitor, and my hubby's laptop.. his is much darker, and such a subtle change would not be noticeable on his lappy. But I am sure it is something you would be able to change to be a more contrasting colour if you wanted to
Heh! Good luck with that campaign. I'd eat my metaphorical hat if more than 1% of the world's displays had been calibrated once since new. Having said that, now that people are starting to run more than one display, perhaps they will start to realise just how far off the majority of displays are out of the box.