Hi, can I read your e-mail?

So, there's a lot of controversy over G-mail, Google's new free e-mail service where they read your e-mail and send you ads based on your e-mail.
And Volokh's position is if you don't like the privacy invasion, don't use g-mail. For the most part, that's a great idea. The only problem that I have with that is the possibility that mail sent to the address would be read regardless of the author's intent for privacy to be maintained. Of course, e-mail in and of itself is fundamentally unsecure, but the point here is that while in other systems, your e-mail COULD be intercepted and read, in g-mail, your e-mail WILL be intercepted and "read" by a program looking for keywords. And if I send an e-mail from my school account to someone using g-mail, that mail will be scanned for keywords, and Google can do anything they want with it, including submitting the information to the government at a mere "request". (See Google's privacy policy.) No warrant, no disinterested judicial gatekeeper, they just ask for it, and Google turns it over.
Scary.