I have played against Poker Bots in Poker Academy Online. The creators of the software play them against the "regulars" to try and inprove their software (their algorithm or engine is used in the new XBox Poker game coming out). The limit bot is excellent and is often near the top of the standings althought the competition is no doubt weaker than some of the better limit games. The no-limit bots are not that good however and are pretty easy to beat if you observe their behaviour - they seem to have little or no randomness i.e. if you bet at them and they have little or nothing they fold. My strategy against these bots is to wager immediately if the bot checks - they always seem to fold. I am sure other bots are different but programming a bluff into a bot would be tough which is why I suspect that limit bots are the only ones that are feasable right now.