Yay found an interview which pretty much confirms that the next ep will be pets and we have horses.
From Sim Programs http://www.simprograms.com/?s=sims+3+unleashed
It was supposed to be published on June 3rd apparently. I hope this isn't fake

An interesting find! :D although it's wary days, Im already hating the idea of Ben bell coming back and screwing this over... 'players can now play their pets stories..' erm. What is that about? I don't really want the pets to have their own thoughts... :/

Wow! That's really generous of them to post!

it's just fancy wording for, "You can control your pets now like you control your sims."

Not really a new feature seeing as you could do it in TS2 with two cheats, but anyway...
I'm really looking forward to more info on this expansion. Hopefully EA will realise where they went wrong with Pets and fix it.
Working out the whole boundary issue with pets will be a little difficult. Do they limit the pets to stay on the lot if their free will is set or do they let them roam free? And what about strays? I don't want Ronroneo the cat out there on his own in the cold!

I kinda liked how we couldn't control pets.. made them more unpredictable. But it'll be a cool feature.

But I don't want to control pets. It's hard enough trying to control my sims. Oh well. Maybe it'll be okay.

There's that.. but hopefully the freewill on them is good. If it is, maybe you can let them be.

Maybe it's just the way this interview was worded....but why do I get the bad feeling the only "pets" in this expansion will be Dogs, Cats and Horses?

I'd like to see pets like Rabbits, Guinea Pigs, Hamsters, Lizard, Snakes, Tarantula and maybe a pet chimp (that's probably pushing it though) Even if they were just items like the fish tanks it would be great.

I hope we'll get some sort of dog/cat competitions and maybe even horse jumping/racing. (Probably hoping too much though. :( ) I'd love a new lot as a sort of horse racetrack (with horse jumping facilites) Then sims could bet on which rider/horse would win. A sim could have a lifetime wish to be like a champion jockey. Ooh I'm getting ahead of myself.

Also wonder if we'll see the return of Werewolves.....one thing that always annoyed me was how a werewolf could attack your sim (without warning) and get a negative relationship while vampires couldn't do the same. :(

Overall looking forward to this, be nice seeing the pets wandering the neighborhood.

I'm glad this was finally confirmed as an expansion. Don't care for the standalones, though. I hope the werewolves are done well, or if it's not werewolves, that it's mermaids or centaurs.

I've always wanted harpies for some reason....I think I like the idea of having feathered bird sims.

On the leaked trailer they showed a snake in the background. If you watch it again then look next to the sofa when the family are sat on it. I'm sure we will get other caged animals too, they would be easy to add onto the game (alot less goes into them than cats/dogs). This expansion should be a step up from the sims 2 unleashed so i'd think it would include most of the same features but with alot more too.

I think having horses in addition to Cats / Dogs alone is a HUGE change for EA. That's absolutely amazing, and I don't even have a passion for horses. If I remember, Birds and Hampsters were the only caged animals in Sims 2. If we have snakes,why not everything else? What if the EP came with a pet store? wait, every sims game before it had a pet store. OKAY, THERE BETTER BE A PETSTORE, GODDAMN IT.

More proof:

Source?

Definitely needs a petstore. And lots and lots of toys. Would be cool to see 3 different bird cages, aquarium tanks(for either fish or snakes/lizzards), hamster/rat cages. Would be fun to buy a generic hamster cage, and then when you take it home, you can click on it and select "Upgrade $" and it adds some tubes and extensions onto it. And it could have 3 levels to upgrade.

That's coding from the traits.xml file of Generations.

you also have to think, maybe they're adding life stages for every animal species they have. and as far as i remember Pets didn't even have raccoons. besides, they'll only squeeze so many thing into the expansions. otherwise they would've had a DJ Booth and a Mic in late night. [who the hell goes to a club without a dj system playing?] sorry for being off topic and all. it was just a good point :P

What would you guys add for pets outside of dogs/cats?

I'd like to see more environmental animals like the skunks and raccoons. Having bird spawners like gems/rocks to take photographs of for a bird watching skill. Sims could buy an outdoor bird house or bath where different feed/water attracts different types of birds. I'd also like to see squirrels!

I'd like to see more wild animals that can't be tamed, just observed, like the birds, squirrels, etc. that you mentioned. Perhaps a new trait for Sims, something like "Animal Lover" that could be satisfied by either owning pets or observing wild animals. I hope there are more pets for cages besides guinea pigs and parrots -- more kinds of rodents such as hamsters, and more birds such as canaries.