Update:
I went to have my fingerprints taken this morning in San Antonio.
My appointment was for 0900, I was out of there by 0840.
I got to the application support center at 0700 and there were already people forming a line, even though the office did not open until 0800.
Since it was a bit chilly, I stayed in my car until about 0740 and then got in line. There were about 15 people in line in front of me at that point.
Around 0745, 20 more people were lined up behind me and two support center employees came out of a side door with a cart and clipboards. They checked everyone's I-797-C letters and IDs (the green card for Naturalization applicants) and handed people clipboards with a form to fill out (just basic information about yourself).
If you applied for Naturalization, be SURE to have your green card with you. It states on the letter that you need it and they were giving one guy who didn't have his one heck of a time about it (I'm not sure if they ultimately let him in or not).
I do want to point out that they had a sign talking about the terrorism threat level being "yellow" and that because of that only people with appointments for that day were allowed in the office. I'm saying that because in some threads I have seen people talking about going to the support center a few days early and being processed, unless you live close, I wouldn't risk it.
The "yellow" threat level also meant that you could not take in any packages, briefcases, etc. on top of the usual items that you can not take in (cell phones, cameras, recording equipment, food, drinks, etc). They had no problem with me taking a book inside (I had expected a longer wait as I had there when I got my picture and prints taken in 2005 to renew my green card).
Right at 0800, they opened the front door and a supervisor told everyone that people with appointments from 0800-0900 could come in, everyone else was to step to the back of the line.
She asked everyone for their appointment time as they stepped inside the door to make sure only the 0800-0900 appointment people came in.
Inside we all stood in a line going to three employees. The guy I went to looked over my filled out form, looked at my green card, looked at my hands (I guess to check and see if they could get good prints?) and then gave me a number (12).
My number was called around 0825. The girl went over my personal information with me to make sure their system showed everything correctly. Then she sprayed water on a cloth, wet my fingers with it, dried them with another cloth (so that they were just barely damp, which is what their system apparently likes) and took my prints.
She asked me to fill out comment card.
I asked her about the free civics study guide mentioned in the I-797-C letter, she pointed to a box and asked me to grab one.
I was out of there at 0840, I could not believe it.
The study guide is basically the same questions you can find on-line on the USCIS website, along with some more explanation/information about each answer (the booklet states that they don't test on that, but I'm going to study all the info to be safe). There is also a CD in the booklet where they read the questions and answers. Probably very handy if someone has a hard time reading or pronouncing English.
I'm going to call the FBI tomorrow to make sure they got the prints and see if they might have already sent the results back to USCIS (according to other posts, most of them go back within 5 minutes of being received).
Time line:
03/14/2008: Mailed N-400 to Texas Service Center
03/18/2008: Texas Service Center received my application (per the USPS return receipt)
03/18/2008: Priority Date
03/18/2008: Check Deposit Date
03/19/2008: Check Cleared by my Bank
03/26/2008: I-797C- Notice of Action mailed - "You should expect to be notified within 210 days of this notice"
03/26/2008: I-797C- Notice of Action mailed - Fingerprinting Appointment scheduled
04/15/2008: Fingerprints taken
XX/XX/2008: FBI sent fingerprinting results back to USCIS
XX/XX/2008: I-797C- Notice of Action mailed - Interview scheduled
XX/XX/2008: Interview
XX/XX/2008: I-797C- Notice of Action mailed - Oath Ceremony scheduled
XX/XX/2008: Oath