Good questions. I didn't change my type of food (got a family), so I'll eat the same stuff -- but more of it. My wife was shocked when I ate 3 plates of spaghetti, btw. BUT, I found that I've lost all desire for breads, cookies, and that sort of stuff. When I did bite into a cookie my 5 year old daughter gave me, the taste was just too sweet -- blech!! Ori says in the book to eat anything you want, except pastries and that sort of thing.
I like the modified version of the diet, wherein (and he say this is okay) you get to nibble -- veggies, a little cheese, almonds throughout the day. I did the water-only a couple of times and it is BRUTAL!
Remember, his theory is that: Days are for activity, nights are for relaxing and eating. It really works, for me anyway.