Consisted of 2 phone interviews and 1 on-site interview.
1st phone interview was basically a 'get to know you' type of call. The lady from Google was incredibly helpful and kind (and continued to be throughout the entire process).
2nd call was a detailed role-play that involved me being a Googler talking to the marketing manager of a fictional bank. It took a lot of preparation, but it went well. I was invited to an on-site.
The on-site consists of 3 interviews. I thought each one went quite well, if not exceedingly well, and was quietly confident that I would be offered a place. Unfortunately it didn't happen. I think it must have been my lack of experience, but I was very disappointed as I thought I could have excelled in the role. That said, the process was OK, all the staff that I met were nice, and the recruiter in particular was fantastic. I was interviewed through an internal referral. I don't think that they would have looked at my CV if I wasn't referred internally.