The AI is continually improved. I don't remember a patch in a long time where Aaron didn't do something to improve AI performance.
Just don't expect perfection. The AI will always be predictable after you play it enough, it is just a bunch of algorithms you know. MM could make each one a bit different from the others in terms of what exactly they will do, making it harder to make a one-size-fits-all strategy against AI, but that would take a lot of time. He DOES have a day job you know
