For such a large company, Facebook moves fast. I started talking to them end of October and received an offer in mid November. This is an unusually fast and fantastic pace for such a large company!
The process was simple starting with a phone call from a hiring manager. Then I spoke to a recruiter which went over the next couple steps: 1) portfolio walk through (phone call), 2) product critique (phone call), 3) onsite interview where I spoke to about 5 different designers and product managers across the organization. I ended my onsite interview with a nice campus tour and some ice cream which sealed the deal for me. About 4 days later I got a call from the recruiter letting me know the details of the offer and start dates available. It was that fast! I joined two weeks later.
The entire process was probably one of the best interview processes I had ever been through. Everyone was extremely friendly and helpful throughout.