Why Trust Holden?

Holden Caulfield is a very unique narrator.  As established in the famous first line, he speaks directly to the reader, and is aware of the that fact during his narration. He also tells us quite frankly, "I'm the most terrific liar you ever saw in your life."  This statement, in the context of his awareness of the act of narration, calls in to question his reliability as a narrator.  However, I do not think I'm alone in feeling like I can trust Holden as a narrator.  I think this is partially because of the way he speaks his mind to us all the time and certainly doesn't hold back with his criticism of others.  In addition to criticizing others, he is also fairly self-deprecating.

I was sixteen then, and I'm seventeen now, and sometimes I act like I'm about thirteen. It's really ironical, because I'm six foot two and a half and I have gray hair. I really do. The one side of my head—the right side—is full of millions of gray hairs. I've had them ever since I was a kid. And yet I still act sometimes like I was only about twelve. Everybody says that, especially my father. It's partly true, too, but it isn't all true. People always think something's all true. I don't give a damn, except that I get bored sometimes when people tell me to act my age.

As a teenager, admitting to acting like you're twelve is pretty significant, as we teenagers generally look down on younger kids and their behavior.  Holden also calls himself a moron repeatedly while discussing his flunking out of school (again).  I think Holden's self-deprecation is part of what makes him likable as a narrator and easy to believe.  Holden can be quite harsh in his criticism, for example when he first tells us about Ackley.

He was one of these very, very tall, round-shouldered guys—he was about six four— with lousy teeth. The whole time he roomed next to me, I never even once saw him brush his teeth. They always looked mossy and awful, and he damn near made you sick if you saw him in the dining room with his mouth full of mashed potatoes and peas or something. Besides that, he had a lot of pimples. Not just on his forehead or his chin, like most guys, but all over his whole face. And not only that, he had a terrible personality. He was also sort of a nasty guy. I wasn't too crazy about him, to tell you the truth.

Hearing all of Holden's thoughts almost makes one feel like a co-conspirator of sorts, getting all the dirt on the people in Holden's life.  Also, he is criticizing pretty much every character in the book including himself, but does not criticize the reader, which, I think, endears him somewhat to the reader.  When I think about it logically, I have very little reason to trust what Holden tells us, but his familiar voice and understandable tiredness with the world around him lure the reader in.  Do you trust Holden as a narrator?  Is there a specific reason you trust/mistrust Holden?  I have had trouble identifying any specific reason as to why I feel like I can trust Holden's narration, but for some reason I do.