I had a similar experience. Google's interviews were generally great (and the interviewers were kind -- it might have helped that I generally did well in them), but the overall process was far slower than some startups and I eventually had to shut down the process at Google to take another offer that was too good to turn down.
The bottom line is that, unless you request everything to be expedited from the beginning, it can take a few months to finish the entire process with Google. Even requesting a schedule change to be made would take about half a week for me. At least that was my experience -- I can't speak for others.
>it can take a few months to finish the entire process with Google.
That is not too bad for such a large company really. Personally I have always worked for small software companies where the hiring process frequently consists of one interview, a bit of a programming test and an offer all concluded in 72 hours (frequently less). Compared to that a few months seems slow but I once had a friend get hired as a trader at a huge international financial organization and that took a glacial 6 months.
Whats more there was the expectation that you would more or less just walk out on whatever job you happened to have accepted in the interim, get on a plane and fly to where they wanted you as soon as you finally received an offer. Looking back on it I suspect that agreeing to that was itself part of their selection criteria.
The bottom line is that, unless you request everything to be expedited from the beginning, it can take a few months to finish the entire process with Google. Even requesting a schedule change to be made would take about half a week for me. At least that was my experience -- I can't speak for others.