I won't repeat the (well-deserved!) accolades. Rather, I write to ensure that potential buyers are aware of one particular feature which is as profoundly helpful as it is unique. Each bird discussion includes the assignment of a V.I., that is, Vagarancy Index. This is best explained by example.
... You're looking out into your yard, and see a new bird (new to you, that is) around the feeder area. You digest its markings, then flip thru a field guide or two, trying to confirm an i.d. You're just about sure that it's, say, a white-throated sparrow, but the maps in your state guide AND a more enlarged regional guide indicate that this particular sparrow would only show up in your neck of the woods, if at all, during the winter--- and it's the dog days of July...
In the past, I would have immediately assumed I was wrong. But instead, I went hunting thru Dunne's Essential Field Guide Companion. I learned: the white-throated sparrow is so extremely likely to be found outside the areas depicted in field guide maps, that those maps become all but irrelevant as regards that particular type of bird. This happened again just last week, as regards a black and white warbler.
In other words, despite being relatively new to the birdwatching hobby, my passion grows as I get confirmation-- from an expert-- that I not only have a clue, but sometimes, I'm right on the money, even when the field guides would have me believe otherwise! Therefore, this is the most aptly titled book you will ever encounter, and I can say, withOUT reservation, that it truly deserves a spot on your bookshelf.
A diplomatically stated postscript: I learned about this book, published this summer, after running a keyword search on BIRD at DiscoveryChannelBookClub.com. (2d page of results hitlist)