An absurd story about Mitt Romney and "animal abuse" has remarkable news traction as it appears to be hopelessly misreported, especially the time frame (I thought this happened last week until I read the details!). The Romney family *over twenty years ago* had a dog that enjoyed riding in a kennel strapped to the roof of the family car. "Forcing" the dog to ride on the roof has been implied where it seems a lot more likely that the dog, Seamus, liked to ride on the roof during family trips.
This is probably an example of some sort of odd "hit job" by opponents.
Anne Romney addresses this over at the Romney blog, though probably too weakly given the attention this continues to get on TV, Time Magazine, and elsewhere. Stories like this are things people can emotionally latch onto and it's important that the campaign at least does more to point out the absurdity of the allegations of animal abuse. Even Tucker Carlson said that Romney's probably "lost his vote"!