What exactly is the Kelley Blue Book?

A quick post today about the Kelley Blue Book (KBB) car values spouted off by used car salesmen: don't believe them!
Here's the little known fact: KBB values represent the average asking price that other dealers have set, not the actual sale price. If you actually pick up a Blue Book it says so in the fine print (also on their website if you look hard enough): "The Kelley Blue Book Suggested Retail Value is representative of dealers' asking prices..." So basically the KBB values have little meaning to you the customer. The only people they are useful for is the used car dealers, it gives them a "number" they can put on the car as a starting point.
The bottom line: if you think you got a deal because you got a car for a couple hundred under Blue Book, you've been had.
There are other better sources of data you can use based on actual sales prices, not asking prices. My favorite is Edmunds.