Two stages, both general interview questions with a technical portion going through a case study. The first stage included 3 maths/logic based questions. Both interviewers were professional and I felt relaxed going through the case study with them.

Two interviews, each consisting of some general CV review and 'why this company, why this role' etc, some GMAT questions that you will have already done in the online test and a case study in either SQL, XML or neither. Depending on the interviewer they will talk you through the case study sometimes giving you the answer, or they will not help you as much and watch your process. Having two interviews means that the chances are in your favour of getting a good interviewer.