In her Twisted nether Blogcast interview, one of the things Ancient wished for was a dog vendor. Or more dogs in the game. And it appears, that Blizzard must have listened.
Firstly, you can get a dog on your farm. A real dog. You find him as a quest in under a bush when your'e flying around the valley and then you end up with a dog as a permanent fixture there.
Secondly, there is an achievement in Mogu'shan vaults that you get from killing the Stone Guard (the dogs) that I wrote about in my last post called Must Love Dogs, where every member of the raid has to have a dog vanity pet out. There are more dogs than I thought!
And thirdly, there is Humane Society, the achievement in Scarlet Halls where you kill the Houndmaster without killing ANY dogs in the instance. I haven't done that yet but I think the next time I wander in there in a guild group I am doing it!