The Sims 3 Pets looks exactly like The Sims 3 does with the exception of the added pets, which is quite a lot actually. There are so many dog breeds, over 90 of them, that you will spend months if you want to try them all out. If you buy the Limited Edition of the game, then you'll get 10 extra exclusive "Rare Breeds" as well and funny enough, most of those were some of my favorites. They add things like a "Panda" and a "Tiger" coloring. There aren't quite as many cat breeds to choose from, but there aren't as many cat breeds in the real world, so you'd expect that. There are still about 30 and I was impressed with how well they managed to make them all look different. With both the dogs and the cats, you can have a lot of fun seeing what one coloring would look like on a different breed under the Coat Option. Things like a Doberman coat on a Pug are just entertaining. There are also really nice details about the game that I love, like the fog rolling in on the mornings. It's really cool looking and really adds to the mystery stories and ghost hunting.
I find that I need to add my own background music while I'm playing The Sims 3 Pets. You can have the radio on, but if the Sims are sleeping, they'll turn it off and the volume changes the further away your cursor is from the source. The characters speak Simlish, but if you have things on the very fast speed, it feels like you're missing a lot of sounds as the Sims talking skips a lot. It is quite amusing to listen to the Sims' language though. Sometimes I would leave it on normal speed just to hear their conversations.