These posters for Horton Hears a Who are in many ways typical of animated movies. Cuddly adorable characters standing against a background made of a bright color.
The character posters are quite sparse, with a very small title treatment and with the character themselves often not occupying that much space in the poster. But I think they work quite well, in great part because the characters are so interesting to look at. They are filled with nifty visual details and have amusing expressions. The sparseness gives the posters a more unique visual identity and helps to maintain the focus on the characters. And like Chris says, their design clearly associates them with what we came to expect Dr. Seuss’ characters to look like.
I do think they overdid it in the the ensemble poster tough. I like staring in a sea of orange as much as the next guy, but it’s not a great way of selling the movie. And the details that made the characters pop out in the other posters end up getting lost when you have a bunch of small versions of them close together.
Still a good effort overall tough.