This is the Starcraft 2 AI at maximum difficulty. I have little reason to believe that the release AI will be much different since the game is already shipping soon and the data gets finalized before that happens (aka gold). Blizzard would not have included the AI in phase 2 if they did not believe it was ready.
It is not ready.
This is a small demo I did on some of the sc1 insane AI's created by myself, Myk, Ashara, and Bajadulce. They range in difficulty from strong (Zbathwar) to absolutely insane ("Opium" Hammer, ZAPOC). These were created within the restrictions of the SC1 engine WITHOUT BWAPI. In sc2, creating an insane AI that functions like these, without the sc1 hardcoded issues to stop you, would be very easy if you know Galaxy.
When it comes to Blizzard games it has
always fallen on the end user to fix the mess left behind by lazy developers. In sc2 this will be no different.
However.
Sc2 has one thing that wc3 and sc1 do not have. A largely softcoded AI whos core aspects are very open. After studying the galaxy files for a short time with HKS, I am sure that even I could improve the insane AI to the point of creating a true, genuine killer. It's not something I plan to do any time soon, but it's on my list to attempt in the late future.
I have written up documentation of what I'd do given a chance to make something in sc2's AI, plans I have never forgotten about, merely laid in the backburner. I am not fond of sc2's gameplay, but creating something like ZAPOC could be interesting. However, I'd have to figure out a way to prevent the wasteful APM spam that kills performance before I investigate creating AI.
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