You're not a programmer quite yet. I like to think of this book as giving you your "programming brown belt". You know enough to start another book on programming and handle it just fine. This book should have given you the mental tools and attitude you need to go through most Ruby books and actually learn something. It might even make it easy.
Rob says: For fun, I recommend you check out Why's (Poignant) Guide to Ruby: http://mislav.uniqpath.com/poignant-guide Most of the actual programming content will be review by now, but Why is a brilliant mind and his book is a work of art. Check out some of his open source projects, which are still floating around. You can learn a lot by reading his code.
You could probably start hacking away at some programs right now, and if you have that itch, go ahead. Just understand anything you write will probably suck. That's alright though, I suck at every programming language I first start using. Nobody writes pure perfect gold when they're a beginner, and anyone who tells you they did is a huge liar.
Finally, remember that this is something you have to do at least a couple hours a night for a while before you can get good. If it helps, while you're struggling to learn Ruby every night, I'm hard at work learning to play guitar. I work at it about 2 or 4 hours a day and still practice scales.
Everyone is a beginner at something.