The guys at gSchool believe strongly that truly learning everything online is really hard. The instructors are world class - IMO that will make all the difference.
Also, there are people who have learned everything online. They are out there - thousands- heck- tens of thousands of them on the web. Granted, maybe gSchool will help educate some people who can't learn themselves. To those people the 20k will be worth it.
I personally am #50 on the Rails Contributors list all-time, so I know a thing or two about Rails. ;).
> To those people the 20k will be worth it.
While there are many people who are able to learn online, there are many that are not. Also, our schedule is just a tad more intense than most autodidacts go for. And the money isn't worth it just for money: it's for cred. I once had a funded startup, and the fact that we went through a YC-like program opened many doors, simply due to social proof. Those who teach themselves have to gain this proof some other way.
I'm the lead instructor for gSchool, Jeff Casimir. I've been teaching Ruby since 2005 and started Jumpstart Lab in 2009. I have both more classroom experience (total) and more hours spent teaching these technologies than anyone in the world.
I wish there were dozens or hundreds of people learning these skills by themselves on the web, but it's just not happening fast enough. The talent shortage is the #1 problem facing most small software businesses, and there's no fix in sight. This is just our little contribution.