I'm tellin' ya, this weeks episode was so damn awesome. One of the reasons I REALLY like Jack Bauer, is 'cuz of his quick and smart thinking.
When he noticed no one at the table where the guard was supposed to be, he quickly knew trouble was afoot. And when trouble showed up, he quickly figured out that someone was double-crossing CTU (Again?! At least it is still awesome.) But for next week's episode, when they show they're arresting the wrong person (we all know who it is, really), only two things come to mind:
1.) They really think it's that girl (I forgot her name- the one that had that little "fued" with Chloe), and they do arrest her. Meaning that the "new girl" finds out about it, and makes it look as it's that other girl.
or
2.) They figure out who it is, and pretend to arrest someone else, trying to psyche out the real spy.
But I doubt it's the latter. Knowing how the show works, it can be either or, 'cuz they always got plot twist showing up when you least expect one.