It does not surprise me that no one voted "no" on this poll.
Every cat and dog I've ever owned has been able to read my and my families emotions. When they see me crying, they will come over and snuggle with me more than usual. My cats will put their paw on my hand and my dogs will rest their little faces on my lap or arm and look up at me as if to say, "Don't cry, mommy. I'll make it all better." It always helps to pick me up.
And I've never had a dog that didn't feel my happiness when I talk excitedly to someone in a room about something great that just happened to me. When I do this with Gigi in the room, her tail starts wagging and she looks around all excited for one of her toys to go grab and bring to me. I guess she associates my happiness with me wanting to play with her.