Stimulating Work? What's That?

Recently caught this post from Sylvia Ann Hewitt. In it, she references some research she's doing for a new book, Top Talent: Keeping Performance Up When Business Is Down. She says that the number one reason that talented people love their jobs--far outstripping compensation and recognition--is having stimulating and challenging assignments. To help prove her point, she adds:

This finding is backed up by our investigation into the commonalities between Boomer and Gen Y workers: Both groups--who together make up 148 million people, or nearly half of the U.S. population--overwhelmingly want their jobs to provide challenging and diverse opportunities to grow both personally and professionally.

I wonder what her research told her about GenX workers? Perhaps that we overwhelmingly want our jobs to provide simple and repetitive tasks so we can grow stagnant and ossify.