Oh, and here is a big shout to those who are filing their GC application:
SPEND $3,000 TO HIRE A LAWYER.
USCIS says you can do this on your own. Right! Look at us....I'm sure there are people who filed on their own and everything went okay. But if you don't have time to read lots of BBS, don't want to carefully read and prepare all the documents, and if you have a demanding job and will be traveling around, and you don't have close friends who can give you their experience as reference, PLEASE hire a lawyer.
Finally, DON"T RESCHEDULE INTERVIEW. Hope this helps some new folks here.
CAVEAT: Don't just hire any lawyer. Hire a lawyer that is COMPETENT in immigration.