I mean, what do we want in a field guide? What's the point here?
I'm amused by all the griping about the new Sibley guide. Not because I don't recognize that there are obvious changes in the color and texture in a lot of the plates but because, so what? Will we lose the ability to identify a Scarlet Tanager in the field?
The holy status earned by the Sibley guide has perhaps worked to its detriment here, as the only place it can go is down. Nevermind that this new edition has added more than 600 new paintings, enlarged most of the images and fully updated range maps, there's a hint of fallibility in this edition and people are overreacting.
Let's just relax for a second. Let's take a second to remember that there are imperfections in this look like there are in every single field guide - imperfections that, for me, result in a much less complete and useful guide than Sibley. Stokes has lighting issues and not enough poses. Crossley doesn't have enough text or ID points. Peterson and National Geographic are too limited. Yet I don't hear people demanding refunds when those books come out.
The fact remains that even in this second edition - especially in this second edition - Sibley remains far and away the best guide on the market. No guide is more complete, no guide is easier to use, no guide presents as many plumages. It'll remain the go-to guide for identifications, and it's still be the first guide I'd recommend to a new birder looking to learn the scope of American birds.