Really pretty casual, though it did can subject matter area questions. Having worked their previously as a sub-contractor meant the management team was already familiar with my work history and skills.

As with most big companies, the paperwork (cover letter & resume) review is handled electronically, by a 3rd party employment agency. So make sure you place in "key words" and address the employment ad directly to make sure you get through the filter. I was then contacted by my would-be manager directly to schedule my phone interview. The phone interview was with 3 people: 2 managers and staff engineer all of whom I would be working with. All interviewers were technical (i.e. no HR). Few days after I was asked to fly down for an onsite interview and tour where I was interviewed face to face with the 3 whom I interviewed with over phone. Nothing was particularly unique or unexpected about the interview process itself. The questions were focused more on my relevant experiences and my motivation. The notice of acceptance does come very late so don't be too let down if you don't hear back in the next day; they do need to get through all the candidates before deciding. The on-board process was extremely slow though (partly because of my relocation internationally).