Interview approved then status changed to RFE

Interview was set at 7:30 AM.
We were up by 5:30 AM to get ready and prepare the kids.
We arrived at the USCIS office at 7:05 AM and they opened the door at 7:15 AM.
It was us and another lady. Then another woman and a gentleman arrived.
At 7:25 they called on my wife and of course did not allow any of us with her (unlike the green card interview).
After 5 minutes, they called the man, and the 2 ladies shortly. A 3rd woman arrived and went inside.
A nice lady (seemed russian) arrived and waited for 5 minuets before she was called.
10 minutes later, the russian lady was out and happy. She was approved. (last in ...first out)..
Few minutes after that, one the ladies came out. She was happy as well.
Then another lady came out and was told to wait for a letter within 60 days.
Then the man came out and left immediately. Could not figure out if he was approved or not..
So everyone was out except my wife and the lady who was there first.
At 7:55, my wife was out. She was approved pending her 3 years anniversary date ( 1/26).
He gave her a paper saying that she will be approved on 1/26/2012 since that is the date she got her GC.
She said he was nice and made her raise her hand to swear to tell the truth.
Then he checked her GC and DL.
He said he wanted to be done with the tests first. 
She answered all 6 questions correctly and then was able to read one sentence and write "The capital of the United States is Washington D.C".
He then went through the application with her. Checked everything and asked her if she has any papers or documents for him.
He had he kids birth certificates from her GC application as well as my Naturalization Certificate.
He only checked the infant's birth certificate.
He looked at the document for the speeding ticket.
She said he did not look at anything else other than asking if she had a recent mortgage statement (which thank GOD, I printed for her just a day or ago).
The rest of the time he was chatting and asking about the kids and school ....and her dad's visit in the summer....
He then said he had the approval ready but cannot do anything until 1/26 to meet the 3 years anniversary.
HE gave her a letter saying a decision cannot be made now but he wrote next to it that approval will be made on 1/26/2012.
That is it...

Good luck to everyone...