Does Codeschool have as many people signed up as codecademy? That could be one reason for the press. I would guess Codecademy has more users because it's free and you can start learning within 10 seconds of landing on their homepage.
tryruby.org is totally unrelated. It's not directed learning - it just drops you into an REPL, what good does that do people who have never coded before (the primary audience of codecademy)? It has a help feature, but it's clearly not the main point or call to action.
Codecademy instructs you immediately. Tryruby has a tutorial hidden as a "help" link among other identical-looking links. It is not a clear call to action.
