Even more than what ESPNU meant to coverage of college sports, the launch of ESPNRise.com is a pivotal event in the brief history of high school sports as spectator sport.
It'll be interesting to track. The site is heavy on the "social media" content and glitzy design -- but light on the meaty state-by-state news (with appropriate implications for colleges in recruiting battles) that I think fans of high school sports want to see: News, rumors, rankings.
Also, I believe it's only a matter of time before Yahoo takes Rivals free, as a counter-move. The subscription revenue Yahoo earns can't possibly top the page-view revenue they would see.