First they asked to submit a solution for a pretty interesting NLP challenge. I enjoyed it.
Second, we met via skype for an hour of technical and general questions.
Third, they asked me to come for an hour and a half to meet different groups of people for 30 minutes each. There was no particular theme, organization or goal of each team. Most people had not prepared questions, it felt more like they were sending odd balls rather than systematically looking for a suitable candidate.