I was so proud of Jack for most of this season too, because it didn't seem like he was falling for their mind tricks. And they were laying it on him pretty thick! I'm mad at him for falling for Juliet in the end like that, no questions asked, but I suppose it makes sense. Both in the characterization of Jack, and for the plot as well. Honestly I want to smack Jack, and don't understand why none of the other losties didn't do that immediately.