After being scouted on LinkedIn, I had a brief phone conversation with an in-house technical recruiter. She was polite and courteous. I had a 45 minute technical interview that started with a description of previous experience and concluded with a coding challenge. The interview went well and I was invited for an onsite in San Francisco.
I had already accepted another offer, so I told them so and they told me to keep in touch if anything changed. Fast forward a few months, and I was unsure about renewal of the contract I had accepted, I reached back out the technical recruiter and, to my honest surprise, they invited me onsite with no additional phone screen necessary. This impressed me.
Now for the onsite: It was scheduled for 4 hours: 4 one-hour sessions, with 15 minutes for wrap-up. Everyone was very friendly, and professional. The culture was very inviting and the technical questions were very balanced; equal parts previous experience, technical breadth, and programming competency.