I had a 11 AM appointment (ND-4/6/2004 at VSC) via infopass but showed up at 10 AM just in case.
1. The guard at the building entrance asked me to enter at the beginning of the Q since I had an infopass appointment.
2. In room 310, I stood in the line just like everyone else. Got a ticket at 10:30 and headed to room 900 on the 9th floor.
3. My number was called at 11 AM and I handed my infopass appointment sheet and filled out 765 form. The person at the counter asked me to wait for the number to be called again.
4. My number got called again (at another counter) at 12:45 and the lady took my fingerprint and asked to sign on a sheet of paper.
5. Got called again for the picture at 12:55 and was handed the iEAD card valid until April 2005 at 1 PM.
I was a tick frustrated with the wait time despite the infopass appointment. Apparently the appointment gets you into the building without the hastle of waiting for hours outside the building and that's that. Once you are in, you are in the line like everyone else. No priority basis due to the appointment.