This will be a long post. I watched the live feed from EA games at the E3 Convention as they discussed what will be in the Sims3 Pets.
Pre-ordering from Origin.com, (used to be EA download manager), gets you the limited edition. The limited edition comes with features that cannot be bought anywhere else and with special items such as a shop where you will be able to have your own store to sell pets and supplies and a special dog collar. They showed them as being for people to wear but not sure if that is what comes with the pre-order or if it's just for the pets.
All breeds of pets will be available.
All pets will be played just like any other Sims. You give them traits, use CAS to create them, can modify them and mix them. Forinstance, a poodle can have dalmation spots, a dalmation can have chow fur, and YES Schip, there will be Schipperky dogs. (sp?) Pet will have a regular life span as any Sim has, starting with puppy, kitten, whatever the baby pet is to elder. They will age and they will have genetic traits that can be passed down. You can cross breed them, but I believe that is within the type of animal, ie. dogs w dogs, etc. So you can create your special crossbreed mutt or make them a champion of your special registered breed.
They will be able to have jobs! Yes! Your dalmation CAN ride on a fire truck! Yes! Your German Sheperd can become a police dog.
There will be accessories that come with the game.
There will be a new town.
There will be quests.
They will have skills
They will have traits, likes, and preferences just like other Sims.
Any questions? I've already pre-ordered. I felt it was really worth it as this EP looks like it will have so much content to make the game even more fun. Can you say dynasty? WOW! Metro, you are sooooo going to have to put your thinking cap on for even more challenges for us now.