Interesting! I didn't know that, and that makes a lot of sense.
If I were to restate my objection more strongly, I'd say that parrots also seem to exceed chimps in language capabilities (chimps having six billion cortical neurons). The reason I didn't bring this up originally is that chimp language research is a horrible, horrible field full of a lot of bad science, so it's difficult to be too confident in that result.
Plenty of people will tell you that signing chimps are just as capable as Alex the parrot - they just need a little bit of interpretation from the handler, and get too nervous to perform well when the handler isn't working with them. Personally, I think that sounds a lot like why psychics suddenly stop working when James Randi shows up, but obviously the situation is a little more complicated.
I'd strongly suggest the movie project nim, if you haven't seen it. In some respects chimpanzee intelligence develops faster than that of a human child, but it also planes off much earlier. Their childhood development period is much shorter.
To first approximation, general intelligence in animals can be predicted by number of neurons/synapses in general learning modules, but this isn't the only factor. I don't have an exact figure, but that poster article suggests parrots have perhaps 1-3 billion ish cortical neuron equivalent.
The next most important fac...
At some point soon, I'm going to attempt to steelman the position of those who reject the AI risk thesis, to see if it can be made solid. Here, I'm just asking if people can link to the most convincing arguments they've found against AI risk.
EDIT: Thanks for all the contribution! Keep them coming...