The Wall Street Journal had an article on youth baseball participation earlier this year:
http://online.wsj.com/article/SB1000..._share_twitter
As someone who has worked in local government for 10 years, I can say without any hesitation more kids are playing soccer. Why? More action, cheaper and the games are shorter. When they kids are getting older and decide what game they like best (and what they are good at), they follow in that direction.
Concerning economy, it will recover. When there was the change from agrarian to industrial society, there was economic issues. We are in the midst of a change from industrial (manufacturing) to service delivery. People need to be retrained and re-educated.
Concerning cards, I see the market as more "collectibles" than cards. Show someone an REA catalog and they will read it cover to cover. It just takes a spark to get them involved.
The internet IS the marketplace. I got back into the hobby 4 years ago (I am 34) and have never been to a show or card store.