I don't thing it should be legal to call a cellphone number and hang up without identifying yourself or at least saying wrong number. It scares people. It is harassment. It infringes on our right for privacy. And it certainly won't reflect favourably on their companies reputation from a marketing perspective.
I got that call too and I called it and it is a survey just like ash said it was. Don't you just love it when you answer the phone and there is no one there?! How can I stop this from happening?