Dogs are way cooler! And cats are jerks! ;)
Let's imagine cats and dogs were people! You come home after work and open your front door...
Cat scenario:
"Hello Honey, I'm home!".... silence..."Honey?" Still no answer....
You put your jacket on the wardrobe and enter your living room. There she lies on the couch, no reaction. You take a seat next to her to greet her and she stands up and goes out of the room... Well, f*ck you too!
Dog scenario:
"Hello Honey, I'm home!" She runs to the door and you can see in her eyes that she really really missed you! On the way to you she bumped into the wardrobe boing
"Oh! Ahh, uhhh, that hurt a little bit but I don't care. You are finaly back!"
"Yes Honey, how was you day?"
"Meh, it was boring! So I decided to return to my research about toilett paper... I haven't cleaned up everything and I think I ate some but now let's go to the park! Really, the park is awesome! Let's go! Let's go! Let's go! Let's go! Come on, what are you waiting for?! Let's go!"

I let you decide but I prefer these clumsy idiots with their big hearts :)