My GC case has just been approved today. I thank all the information I got from here. So I also want to share my information.
NIW, VSC,
File I140: 12,2001
I140 approved/ File I485 : 3,2002
FP: 5,2003
Interview: 3,3, 2004
Approved/Passport stamped: 3,3,2004
I am in Boston. My interview is also in Boston local immigration office.
Hope this helps. Good luck everyone.