I am currently going through Miguel Grinberg's Flask dev book (the early O'Reilly version) but I had considered diving into Django instead. My rationale for making this choice basically came down to seeing that Flask doesn't "come with batteries", and I thought it would be more educationally valuable to have a broad understanding of the various components of a web app before trying something like Django which apparently does things that Flask doesn't. (I may be off-base here, of course -- I know that I don't know what I don't know!) All of which is to say that I hope you give some space to at least discussing "why Django?". Good luck!
Yup definitely. The fact that Django comes "with batteries" is one of the reasons why I'm choosing it — for people with less of a tech background, I'm hoping to show the "how" first (getting the web app working), and then work on the "why" in the latter half of the book. For me, seeing things work first was more encouraging and got me more enthusiastic about learning more. I'll definitely expand on this more in the book, and thanks for the comment!