Timing is everything in all aspects of life. being a Graphic Designer that make us more responsible about timing, we have due dates we have to know and understand what is happening in the world at this time so we can relate and not affect negatively by unknowing certain issues.
But there always have to be limits, for example in advertising's as he have recently viewed about the H1N1 virus, i believe media have talked about it so much that they freaked out people all around the world, i think they have exceeded the limit, now it is not only about making people aware of it, though we know that the flu that comes after Hajj is more dangerous!
Also about timing, designers always should know when and where to publish the work. for example: now we are in the hajj month, people from all over the world are here. designers and media have started talking about hajj, how to do it, what is right and wrong, and many other instructions for people who have not been here before and they have showed it in different languages. that went so good with all pilgrims, and it was in a good timing that its the time to know all this information and at the same time not to forget it.
here is a link about some of the Ads they have done for Hajj: