I read that for Shogi, humans are forbidden to play against computers. This is somehow admittance that computers are at least of the same level if not stronger. So I guess that for games with complex pieces, computers dominate right now. But yes, Go is still dominated by humans... for how long? :)
There's no computer program for Twixt yet which plays much better than amateur level, the best one that I know is jTwixt. But there also hasn't been such an intensive research in Twixt-AI as for example there is for chess or go, and there also aren't programs that run on huge computers and take advantage of it.
Havannah programs are good, but the best humans (not necessarily including yours truly) are still better.
There has been quite some AI action around Symple in the 2013 CodeCup Challenge. I do have the winning program and I usually win. And I'm by no means an expert player, so there seems to be some leeway there. You can find Symple at mindsports.
I feel that eventually every abstract strategy game that allows humans to excel in it, will have to face the emergence of programs that excel even more in it. That would include Go. This may help players to better understand their game, but it may also separate the fields in actual play. If it's no use anymore to play against a program because it is superior, then it's no fun anymore either.