I've had a different view of small bird brains vs. large human brains in light of the computer chip.
Like with a really fast, optimized gaming system such as a PSP or Nintendo, the bird's brain seems to be optimized for graphics (eyesight) and nimble manuevers.
We're nowhere near as fast or acute visually, but we can carry out a much larger set of instruction sets, if you will.

I believe one prominent theorists prediction is that the equivalent computing power of a human brain could fit inside a cubic centimeter-sized nanocomputer.