First off-both taste great. I'd be happy to snack on either or make a really amazing pie crust from them.
The darker coloured grahams contain molasses and use whole wheat flour. The lighter ones use specialty graham flour and are made crisp and light with the addition of an egg. It's a mater of style. The molasses/whole wheat crackers were harder and heavier-the others had a melt-in-the-mouth quality of a thin butter cookie.
The Lighter Graham cracker recipe came from The Prepared Pantry, and may be found(with helpful photograph and details) HERE.
The molasses version came from Bakingsheet, and may be found HERE.
The molasses crackers were prepared in my food processor which worked much better than I expected. Rolling the dough out and then chilling it also made for more uniform and easy to handle slices. Of course, they are homemade, and that look out to be reflected in the varied sizes and not-so-perfect piercing of holes.
I needed about two minutes more on both recipes in my oven, which runs pretty true to temperature.