are smartphones bad for you?

Smartphones are still pretty new, and the fact is that we are not sure how they affect the way we think.  Some people are so addicted to their phones that it seems like there is a real problem.  Then again, as THIS ARTICLE points out, different generations of parents have been afraid that lots of things-- like TV, video games, the telephone, dancing, and even reading (!) would hurt their kids.  Is the smartphone different, or do you think we've just found something new to worry about?