There was no mail service yesterday because it was MLK day, right?  I just checked the DC on a book mailed to me and the latest update says "NO AUTHORIZED RECIPIENT AVAILABLE (56) at 11:54 AM on 01/21/2013 in ATLANTA,GA 30306."  But according to my google search, they shouldn't have even been attempting to deliver to me because of the holiday.  I also am a bit unsure what that status even means.  I did check my mailbox just in case this morning and there was no notice left or anything in the box.

I'm not sure about your particular case but UPS did deliver yesterday.  I saw the brown truck in my neighborhood.  I also live in Atlanta.  Maybe your book was sent by UPS instead of USPS????

No, it was definitely sent USPS with PBS Postage.  Hopefully it will be delivered or updated today.

They did pick up from some blue boxes on the holiday. I had 8 packages to mail, so I put half in the box near my home and half in the box that's right outside my office. I was surprised to see the office packages were all scanned Acceptance and En Route on the 21st, while the home packages have not been scanned at all yet.

Shouldn't have been any delivery services on MLK day, it's a federal holiday.

Maybe that means it was delivered to your PO, but no one was there to scan it? Did you get it today?

I did end up getting it on Tuesday.  I tried to call ask usps and see if they could maybe figure out what happened, but because it was a 9452 number from here, they couldn't look it up in their system.