So nobody is paying attention to my comments apparently.
FYI: Killer Whales, despite the name, are not whales.
They are far more closely related to the common dolphin than to whales.
In the same line of thinking others have posted, like dolphins (and most porpoises), they are very intelligent animals.
Also, one common theory is that the Canine genetic line was once shared with the porpoise genetic line (common ancestor), which explains the social behavior and the intelligence that often goes hand-in-hand with that behavior.
A lot of the differences in our attitude toward them just comes with the societal endearment and more importantly, the nature of the animal.
Animals like dolphins and orcas are hard to domesticate because there is, well, an obvious natural barrier to such an idea. They breath like us but are still creatures of the sea, so how can we treat the animals like we would a domestic animal? They are of the same mental capacity in most ways, but we can't possibly give the same emotional attention for said obvious reasons.
Most people give dolphins credit where it is due, and recognize their intelligence. Orcas, apart from the people that are more involved with them, don't receive that same credit.