This book is a great idea, and overall pretty well executed. The trips are themed and *very* well organized, indexed not only by region, but by season and theme (history, outdoors, cities, etc.). There's a handy "trip planner" with at-a-glance facts about each trip and several maps.
Past all that intro, the trips themselves are also nicely laid out. The first page lists all the facts, a "why to go" introduction, and a map. The text highlights points of interest along the way with interesting call-out boxes included. The last section lists things to do, places to eat and stay, and web sites to visit to learn more. Finally, a very nice closing touch is the "Link Your Trip" for ideas on how to combine this trip with others in the book.
Two drawbacks I've seen so far, though, make this a weak travel guide. First, the trips aren't very detailed, so you'll definitely want to consult other resources (but that's impossibly easy in this internet age).
Second and more important to me, the Mid-Atlantic section is, well, pitiful. They've combined New York, New Jersey, Maryland, Delaware, and Virginia into this section - in itself really odd - but the choices are just plain bizarre (and pretty dull, to boot). Washington DC is given barely a nod, and Baltimore is ignored (except for a crab restaurant). This wouldn't seem so odd if NYC, Boston, Miami, New Orleans, Austin, Denver, Chicago (etc.) didn't all have trips listed ("48 hours in..."). Besides this, the trips they do include are pretty uninspired. Since this is the area I know best, it makes me wonder about the quality of advice for the other regions.
Overall, we'll use this book for inspiration and ideas, but will definitely be using something else for actual trips.