So, I finally came around to watching this at probably the latest time I've ever seen a film, 9:30p. (The first theater I tried to go to was for 8:30, but it was sold out. "Must be that good," I thought at the time.) Looking back, I think it was an ok film that made some great references to the cartoon, like the intro sequence, Peabody making puns and Sherman not getting it, the design of the WAYBAC door, the historical figures acting kooky, even a nod to the original ending with the sweeper guy. The parts I didn't like though:
--Penny: I really think the crew at DW could have used her a bit more; she didn't seem to have a purpose other than the bully-turned-love-interest.
--The origin of Sherman: I know this seems like a nitpick, but in the original show, Peabody finds Sherman getting beat up in an orphanage and feels so much sympathy for him that he adopts him. In here, he just finds him as a baby in a box. Seems pretty generic to me.
--The whole "I'm a dog, so I can't take care of a boy" element: That kinda seemed unnecessary. Peabody is the smartest dog in the world, why would people be afraid of him taking care of a kid? That's like saying, "Oh no, a talking moose and squirrel. They are freaks of nature! We must rid of them!" or something like that. It's like they're putting cartoonish elements in a realistic light.
Other than that, good movie that's stronger than previous Jay Ward adaptations. (PS: What happened to the Rocky and Bullwinkle short?)