I know I've been asking a lot of home related questions, but your responses are helpful!

What do you think of hardwood flooring upstairs where the bedrooms are? Our current house has hardwood downstairs (which I love) and carpet upstairs. My husband thinks instead of replacing the old carpet, we should install hardwood floors. He likes the look of them and thinks they stay cleaner than carpet. My concerns are that the bedrooms might feel less warm/cozy (although we could get nice rugs), and the floors might be slippery around the stairs causing children to potentially fall. Does anyone have hardwood floors upstairs (or in the bedrooms if ranch style house)? If you do, do you like them? If you don't, would you consider it?