Had a developer friend inside refer me. Received an email from an internal recruiter about a week later to set up an initial interview by phone. In the phone interview, I was asked a couple short background questions and we jumped directly into analyzing a Google product of my choice. I chose GMail, and proceeded to discuss what I like and dislike about the product, and ways I thought it could be improved.
I received a follow-up email a few days later expressing interest in scheduling on-site interviews. We worked out a date for two weeks later. The on-site interviews included 2 product managers, a VP-level product director, and a developer.
The product manager interviews largely followed the pattern of the initial phone interview. Very little if any time was spent discussing my background, interests, and skillset. One PM began the interview by introducing himself by name and immediately asking, "What's the best idea for a product you have?" I'm a very forward, extroverted person, but the interview style of these 2 PMs was very off-putting. The senior director was a much better interview, including a real-life PM scenario about scoping and analyzing a proposed new feature instead of 30 minutes of fantasy product analysis.
The developer interview, which was last, included one broad technology question that was meant to probe for my knowledge of Internet infrastructure and speed constraints, and a programming problem that I bombed.
I heard back within 2 weeks.