The computer can count cards perfectly and brute force calculate the odds of each possible hand. The computer has no "tell"; but on the other hand, it probably can't read any human tells either. Over enough hands, the computer is always going to come out ahead, just by better calculation of probabilities. Artificial Intelligence isn't really required to give it an advantage, and other than being able to read the faces and tells of opponents, I'm not sure AI is even useful for poker. Of course, the software is probably also trying to use past bluffing history to predict when opponents are bluffing, giving this somewhat of the flavor of the Rock, Paper, Scissors programming competition (my quick and dirty algorithm sucked at that).