I am just about finished with the book and I just wanted to say thanks for writing this book. It has helped me quite a bit with the architecture and design of a game engine (as well as lots of other things!). I feel like after the book, that I'm going to start making a basic engine following the principles in the book. It's going to take me a while, but I don't mind, I'm really just looking forward to learning more through experience.

I have one question though. I am not really interested in graphics programming, I don't feel like I have enough time to devote to it while in addition working on other portions of the game engine. Would using OGRE be a decent substitute for a rendering engine?

That would make sense. I am primarily a gameplay programmer, and work in UE3 usually. This is going to be a side venture because I feel like I should understand the inner workings of an engine better. I am comfortable with linear algebra and trig. At least the level that a gameplay programmer would be exposed to. I think the 2D direction would be a good idea. If I follow the architecture and design from the book it shouldn't be difficult to substitute another renderer.