nope, sorry, that just not the way its happening...
When a user opens an email message, computers scan the text and then instantaneously display relevant information that is matched to the text of the message. Once the message is closed, ads are no longer displayed. It is important to note that the ads generated by this matching process are dynamically generated each time a message is opened by the user--in other words, Google does not attach particular ads to individual messages or to users' accounts.
How is that different to what I think is happening or what you think is happening? I am genuinely curious.
The important thing is that Gmail is no less (or more) secure or subject to privacy concerns than any other email service provider. I think we can both agree to that. ;-)
Ian