The kids are both loving the latest counting books I picked up at the library; How Do Dinosaurs Count To Ten by Jane Yolen and One Potato by Diana Pomeroy.
One Potato has gorgeous potato-print illustrations of fruit and veggies, and instructions in the back of the book on how to do potato prints. Yolen's book is big fun with wonderful colors and dinosaurs doing things that kids would do, making for silly fun counting (plus learning dinosaur names)!
And, Ten Little Rabbits is from our own collection — from Gramma and Grampa's trip to Bryce National Park last summer. It's a gorgeous board book with illustrations that include Southwestern landscapes, and it depicts Native American traditions and includes rich vocabulary (i.e. anglers, nimble, festive, fleeing, mischief, and messengers) while teaching counting. Madeline especially loves the "Nine festive drummers beating on a drum."