The contents of my emails are exposed to "god know how many engineers and system administrators." I still think I have a "reasonable expectation of privacy" with regards to the contents of my emails. If you hire a cleaning lady and she has access to private letters in your home, does that mean you forfeit your reasonable expectation that those letters are private?
People of course can disagree about what is "reasonable." I personally don't consider my e-mail private, not when a Google engineer has been caught stalking people through their GChats (http://gawker.com/5637234/gcreep-google-engineer-stalked-tee...), and not when the whole business model is built on reading through those e-mails to serve advertisements. I consider that quite different than my cleaning lady incidentally having access to documents in my desk drawer.
