I applied through a staffing agency. The process took 3 days. I interviewed at Google (Mountain View, CA) in Mar 2010
Interview
Went to client site for 1 video teleconference and 2 in person interviews. Teleconference room was not vacated by prior user, had to fall back and just do a phone interview. Went well. Next interview scheduled after 1 hour gap however BOTH recruiters were off site that day and didn't let interview coordinator know. Had to come back another day to meet with them. One interview went well, one was somewhat confrontational (suprising after she had blown me off the first time). Then, took two weeks to get back to me with "Thanks but we have selected someone else". I had heard that Google was tough but fair and decisions were made quickly. Not exactly my experience. I truly had expected more descriptive feedback.
I applied through an employee referral. The process took 3 weeks. I interviewed at Google (Dublín, Dublín) in Aug 2008
Interview
First phone interview with California - but the guy interviewing forgot about me...so I sat at home at the required time waiting for the phone interview to happen and called several times. Eventually heard from him, then 1:1 to interview with 4 different people, seemed unstructured.