First and foremost it was interesting to get a sneak peak of Dean's vulnerable side, even though some of it was beyond ridiculous, but hilarious. It was good to see this facet of Dean's personality since usually Sam is the emotional one while Dean was always the stoic one, with the whole "I'm fine" mantra, even when he was falling apart.
There was an "I quit" speech he did that was absolutely brilliant, had me in stitches. I think some of it went: "You know, normal people run away from scary things. But you know what we do? We go looking for them, we hunt them. I mean, who does that? I'll tell you who does that. Crazy people. We're crazy, Sam." and then there was something else chucked in the middle about a truck-stop waitress with a weird rash.
It was unsurprising in the end to find Dean's greatest fear was Lilith and returning to hell. But the really interesting part of this episode was raised when Dean and Sam were talking about why certain people contracted the ghost sickness. Sam theory was that they were all dicks and then this was never refuted. In actual fact, it was my opinion that these people got the Ghost Sickness because they all had a secret relating to the particular ghost's death. So why did Dean get it when he's clearly not a dick and didn't know anything about the ghost's death? It was revealed during the climax when Dean asked Lilith "why me" and her response was "you know why, listen to your heart."
Unfortunately many of the fans didn't get this. Obviously they were too busy drooling over Jensen Ackles to see the big fat clues the writers put in there, and after the episode aired, lots of people got on the net infuriated over the fact that it was implicated that Dean is a dick. So Erik Kripke had to release a statement to the media ensuring the numerous frothing-at-the-mouth fans that Dean is not a dick and it was never intended to seem that way. So in reality, Dean has some big dark secret about being in hell, never mind the fact that he remembers being there and told Sam and bobby he didn't.
Now I'm dying to know what the big secret is. Apparently it's going to be revealed during episode 10, so I have four weeks to sit here and wait to see what it could be. It just keeps getting better. I guess the writers and creators must be doing something right if they're forced to answer crazy fandom rantings.