Who would use a web based free Email system to send and recieve confedintial private E-mails anyway?
I think that since Google came right and said, "this is what we are going to do" and you click the "I Read and Understand it" checkbox, then why should all these other people care?
Ok, I can think of 1 reason. I have a GMail account and I say "Hey Jo, send me an Email". Jo didn't concent to having his Email scanned by Google. So I can see how that would cause some problems. Maybe google should only scan Email that is from an @gmail.com user. Surely there will be enough of those people to help support Google if they get to offer this service.
On the other hand, why does it have to be any different from how adSense works. Instead of scanning the Email on the server, why doesn't adsense just scan the text when the email is read from the HTML. How is this different? People don't seem to bitch about AdSense scanning their web pages.