At Google I was able to tell if I was going to get the job or not based on how long the process took. I say this because I was interviewed twice by Google 3 and a half months apart- both times a recruiter reached out to me to apply.
The first time, I was interviewed over a 6-7 week period. I had an initial screen with a recruiter, then a follow-up screen with a recruiter (they asked about my undergrad GPA, in addition to asking about my job history!) and then had an in-person Mountain View interview where I met with 5 people, some of them via video conference (which I had never done before and it felt weird then - now it's so natural). Then the next week I had a phone interview with a guy who was the head of a parallel group that my group would be working with. He called me 1/2 hour late, was rushed, apologized profusely, and while I felt good about that phone interview, I felt it would have been far better in person and the phone guy seemed rushed and didn't have it all together - I had a feeling he might be a bit biased against me because he felt chagrined about being late and he associated that discomfiture feeling to my interview. After that final interview I didn't hear back for two weeks so I suspected maybe I didn't get the job. And no, I didn't get the job. But it was a really successful set of interviews overall and I had a good feeling about it throughout the process. I was sad when I didn't get the offer, but I was working somewhere I really liked already, and was just flattered that Google had reached out at all. At least their call made me put together a resume, something I hadn't done in some years.
The second time I was interviewed, the same recruiter called back 3 months later, and said the group that had really liked me the first time but had given the job to someone else really wanted me to apply for this position again and would I consider interviewing for the same position but now it was in a different group and I'd have to interview with different people. I said sure. That time around, I again had another phone interview (after the initial phone consult), then another day of interviews with 6 people. I again felt good about the interview -the difference is this time I got an offer within a few days of the final interview. Yay!
It's amazing how much validation even getting an interview with Google gives you internally (how you view yourself I mean) - to get the job offer was something beyond my wildest dreams.
Now that I'm at Google, I really love my job. It took some time to get to know my job well, especially that first year, and the legal department can sometimes seem a little cliquely when you first join it but that will go away with time (there are people who have worked together for years there and it's hard to break in sometimes)- but I don't think there is another workplace that comes close to it in terms of how it looks out for its employees, and in terms of the intellectual challenges that my job gives me, and I highly recommend it.