Actually, the Tesselate won the latest
AI Deathmatch. For a really good player, even the best TDM AI on high bonus is not a challenge unless the player adds some extra restrictions to how he plays, such as not taking religious and not using training facilities. For a really good AI, wait for SEV - no more inputting numbers into an algorithm, modders will actually be able to write the algorithms the AI uses from scratch. With enough people working on it, this should result is some truly good AI's.