Hello. I registered with PSO a few days ago and have learned a lot already. I've been playing Texas Hold'em for about a year and a half, mostly online and with free local poker leagues, and have seen steady progress. I've even won or placed in a few small tournaments and place in the money in about half the online games I play. But I'm under no illusion that I'm a "good" player. There's so much more to learn and comprehend before I would even consider myself good. And so I'm very appreciative that Poker Stars offers this free online training.
My biggest weaknesses at the moment are understanding the probabilities of the game and reading my opponents. To address the first issue, I'm not naturally math-oriented and I have a hard time figuring out when the odds are in my favor, especially under the pressure of a game. In my case the best I'll probably manage is to memorize the odds from the handy chart provided in the PSO Core course. As regards my second weakness, I'm a somewhat shy person and tend to avoid focusing on people to watch how they play, what their tells are, and so forth. I know players expect to be observed, so that is something I just need to fight to overcome.
I've passed the Basic and Core quizzes but didn't do as well as I would have liked in the latter (I'm sure the probability-related questions are what did me in), so I'll review it and take the quiz again in a few days.