Well I finished The Know It All today. And I will say that I really enjoyed it. There were a couple of errors in it. One where AJ says that Lumber is British for Old Furniture. It's not. Lumber is British for the logs, right after the tree has been cut down. Furniture is still furniture.
I enjoyed reading about AJ's time at the Crossword Tournament, and the time he was on the TV game show - Who wants to be a Millionaire with Meredith from the View. I learnt a lot from AJ, without reading the Encyclopedia Britannica.
Here's AJ's website, in which he mentions some other books he is writing.