Has anyone used the new (5th edition) National Geographic Field Guide to the
Birds of North America? I got an offer in the mail for $29.95 softcover and
$36.95 hardcover, and I'm wondering if it's worth the price considering that I
already have the 3rd edition, as well as Sibley (large and small editions),
Peterson, Kaufman, and Audubon field guides, plus other references. Is there
anything new here that makes it worthwhile? Any feedback would be welcome.