Exactly my thoughts. I'm close to finishing a formal CS education and I've been working on learning Rails (off and on) over the last couple of months. Granted, I'm a full-time student with a close to full-time development internship, so I don't have a ton of time, but I've found a pretty steep learning curve on Rails. There's so many concepts that I haven't and won't be exposed to in my CS education that I have to learn on my own. I'm pretty good at Ruby, but beyond that, I've got a huge list of topics I need to dive into before I feel I could be a good Rails developer.