My less pessimistic (dare I say realistic, ha!) take is that whales will have little of note to say. Complex communication (in contrast to "simple" communication like the evocation of emotions, e.g. fear, anger, sadness, etc.) does seem to require the biological need for it, otherwise the genes that control factors that manifest it ("depth" and richness of sense, proclivity for specific mental models, etc.) do not get reinforced and "bred" into the animal.
The other side to this is that communication is mostly non-verbal. For example, chimpanzees, perhaps the most communicationally-advanced animals, besides us, do have a few different "verbal" signals they use. But there is also a richness of non-verbal communication (body language, facial expression, using their hands, etc.). And then these signals have to be also interpreted by other chimpanzees, thus training them to develop new mental models about these signals (and leading way to complex communication).
Whereas all whales really have are clicks, whistles, and "pulsed calls." Along with a tail with much less dexterity than a hand (but is still used in communicating amongst themselves). The richness of their communication is much less than the chimp, so so far it seems they can only use it for rudimentary purposes (mating, hunting/intelligent organization and navigation, and figuring out who is part of the "tribe"/pod).
But in that vein, they're still closer to a chimp than they are to us. Humans have evolved such complex mental models for the world and other humans within it, that all animals are basically on the same, much lower level in comparison.
On a less relevant topic, whales are social animals that stick together, make close bonds with family, and do have a certain "culture" that gets passed down, and is constantly morphing a la "whale songs." It almost pains me to think about what emotions a whale would feel (if it even does) about friends and family that have been hunted to death.