Hmmm, let me think (it was awhile ago
I think the most important mental shift for me, was concentrating on what TO eat instead of what NOT to eat. My whole life, my diet had been "no this no this no this." For me, SuperFoods was eat THIS eat THIS eat THIS. I made a game to see how many superfoods I could eat per day (I started before the second book, so there were 14 and sidekicks). Each super food + sidekicks counted as "1" so if I ate tomatoes and watermelon (both good sources of lycopene) that counted as 1 superfood. Carrots + orange pepper - 1 (if that makes any sense). So, that would be 2 for the day, so far (in my game, heh)
I was so busy working in Super Foods that there just wasn't space in the day/meals for other stuff. I didn't even start calorie counting until much later in the process (and really to be sure I was eating enough).
I actually MUCH prefer the first book to the second book, but maybe that was because I read the first book first and the second book is VERY redundant (of course, it adds a bunch more healthy foods like onions and garlic!)
I didn't realize it at the time, but for me, SuperFoods was the doorway into Whole Foods. With the focus on fruits, vegetables, whole grains and the de-emphasis on meat, processed foods, I really started eating fresher foods - processed foods weren't super foods, so out went crackers, chips, pretzels, etc. I also started cooking more.
I also eliminated sugar/white flour - WITHOUT TRYING. I had no goal about sugar, it just wasn't a super food. This...was...huge...for...me. It was a complete accident but...wow, a miracle happened for me. All my life, I had suffered from uncontrolled eating episodes. I thought they were random, but they weren't. They were caused by my particular trigger foods - sugar, empty carbs - particularly foods like crackers, chips, packaged cookies (even "healthy" non fat stuff like SnackWells). I stopped eating them and my cravings...vanished. I still get the occasional "mmm pizza" or "wow, a hamburger would be great" but the difference for me has been night and day. I know what it's like to be normal, to have a plan for what to eat for the day, and just eat that. I don't wander into the kitchen and rummage through the frig/cabinets aimlessly anymore.
Sorry if I'm projecting too much of my own journey, I still feel like the day I picked up that book at Barnes & Noble was an amazing, life altering day. I knew, right away, what to do, how I would do it and that it would work. Instead of diets I started "on Mondays" that never came, I started that second.
My plan definitely morphed and changed, I tweaked. I started out eating Yoplait 100 calorie yogurts, I switched to organic non fat yogurt, for example. My journey became more about health (still about weight loss, but really focused on doing right for my body). I added portion control (measuring cups, food scale), calorie counting (Fitday!) and putting a name to what I did a lot of the time (volumetrics - huge pile of broccoli, big stir fry with tons of veggies, etc).
I do think it's important to change a plan to work for you. Read the book, pick out what you like, what would work for you, ditch the rest. This is just about YOU.