My son had his interview today at 9:00 am at St. Louis DO. We came at 8:35 am, and he was called in at about 8:45-8:50 am, earlier than expected. I was waiting for him in the waiting room. In about just 10 minutes he came out smiling. The interview went very well, nothing difficult at all, pretty standard. 6 civic questions, reading and writing something at the 1-st grade level. The IO asked basic questions on his application, asked for documents - DL, passports, GC, and his Selective Service card. My son says that only one thing was tricky - the IO asked him to spell his middle name, which is long and difficult for spelling with some kind of possible English-spelling ambiguity due to transliteration. In our home country this is always a derivative from the father's name, and my son actually has never been using it. When he tried to spell it, he made a mistake at first. The IO was pretty nice to him, and allowed for a second attempt, and then he did it correctly. So he got a form that says that he passed the test and is recommended for naturalization approval.
For more details on this please click here US Citizenship