Horses

Horses were confirmed to be in the Sims 3 Pets when the official launch trailer was released. You saw sims riding around with their pet horse.

At E3, EA announced alot of news to do with the Horses, one being that their were going to be foals in the game, so the horses can breed. Also different age catagories.

Then it was later confirmed that the horses would be fully customisable and you would be able to fully controll them like the cats and dogs.