I don't know anyone who would say that they enjoyed their interview experience at Google. Don't get me wrong, they have some excellent internal recruiters as well as some stellar people on their interview panels. However, the process is long, overly drawn out (in terms of time), and somewhat left up to chance - at least, that's my opinion when it comes to technical roles.
I've interviewed at Google more than once (and been rejected by Google more than once). So, you might say that I was one of those dumb fools who kept coming back for more rejection. Or you could look at it as "Persistence pays off", since I'm currently working for Google full-time. The process started off with a technical phone screen followed by a week of waiting. Then a few weeks passed by while trying to find a mutually agreeable time for the onsite interview. The onsite consisted of 4-5 rounds of 1-on-1 interview sessions (with a couple of interviewers in training sitting in). The technical questions varied from the following: web technologies, databases, coding exercises, logic problems, personality fit, leadership methods, etc., etc. Then after the onsite was over it was followed by (...yep, you guessed it)... more waiting.
I then got feedback from my recruiter (who was excellent by the way) that I needed to do one more interview in order to strengthen my candidate packet before sending all the feedback to a review board. After this, all of the feedback from all of my interviews was sent to a review board (...followed by waiting). Then after passing that review it was sent to a final senior management review board (...and more waiting), and in the end I received an offer.
The process is no fun, especially if you get close to the end and get rejected (which has happened to me) but if you find the right role and get paired up with great interviewers, the odds are definitely more in your favor.