Are you sure about that?
Just being sarcastic as this is the normal procedure with these series. One episode gets you on the edge of your set or hopeful (in this case), the very next episode is like nothing ever happened or was said.
Wasn't there an earlier episode when Castle overheard Becket say she remembered everything about the day she was shot?
Funny you mentioned this, since this caught my wifes attention when Becket said that, getting Castle's attention.