I was referred by a current employee. I applied through my university job board and got the first round interview because of the referral. (I also met a manager at a career fair a week before the interview). The first interview was 30 minutes in person at the career center. Very casual. Felt more like a conversation. He was trying to gauge my interest in the program and how my background would fit in well for the program. He was so friendly and nice; felt like he was genuinely interested in what I had to say and what I could bring to the company. A week later someone contacted me about a background check and scheduling a final round interview in HQ in Palo Alto.
The final round was pretty intense. You start with a writing portion. 45 minutes to read a prompt and write a short essay. Then you have 5 back to back 30 minute interviews. All behavioral. They want to know why you would be a good fit for the company, why you're interested, and what you can bring to the program. Then I went out to lunch with some current members of the program. After lunch, I had a final 30 min interview. A week later, my recruiter called me to give me an offer.
I have nothing but great things to say about the program and the people. I ended up taking another job but I have an incredibly great impression of the company, its culture, and the training program that works to teach and to promote.